Internet DRAFT - draft-suthar-icnrg-icn-lte-4g
draft-suthar-icnrg-icn-lte-4g
ICN Research Group Prakash Suthar
Internet-Draft Milan Stolic
Intended status: Informational Anil Jangam
Cisco Systems
Dirk Trossen
InterDigital Inc.
Expires: May 16, 2018 November 12, 2017
Native Deployment of ICN in LTE, 4G Mobile Networks
draft-suthar-icnrg-icn-lte-4g-04
Abstract
LTE, 4G mobile networks use IP based transport for control plane to
establish the data session and user plane for actual data delivery.
In existing architecture, IP transport used in user plane is not
optimized for data transport, which leads to an inefficient data
delivery. IP unicast routing from server to clients is used for
delivery of multimedia content to User Equipment (UE), where each
user gets a separate stream. From bandwidth and routing perspective
this approach is inefficient. Multicast and broadcast technologies
have emerged recently for mobile networks, but their deployments are
very limited or at an experimental stage due to complex architecture
and radio spectrum issues. ICN is a rapidly emerging technology with
built-in features for efficient multimedia data delivery, however
majority of the work is focused on fixed networks. The main focus of
this draft is on native deployment of ICN in cellular mobile networks
by using ICN in 3GPP protocol stack. ICN has an inherent capability
for multicast, anchorless mobility, security and it is optimized for
data delivery using local caching at the edge. The native ICN (it
runs directly on cellular layer 2 protocols like PDCP/RLC/MAC/L1) or
dual stack (along with IP) deployment will bring all inherent
benefits and help in optimizing mobile networks.
Status of this Memo
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Table of Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 3GPP Terminology and Concepts . . . . . . . . . . . . . . . 4
2. LTE, 4G Mobile Network . . . . . . . . . . . . . . . . . . . . 8
2.1 Network Overview . . . . . . . . . . . . . . . . . . . . . 8
2.2 QoS Challenges . . . . . . . . . . . . . . . . . . . . . . 9
2.3 Data Transport Using IP . . . . . . . . . . . . . . . . . . 10
2.4 Virtualizing Mobile Networks . . . . . . . . . . . . . . . 11
3. Data Transport Using ICN . . . . . . . . . . . . . . . . . . . 11
4. ICN Deployment in 4G and LTE Networks . . . . . . . . . . . . 14
4.1 General ICN Deployment Considerations . . . . . . . . . . . 14
4.2 ICN Deployment Scenarios . . . . . . . . . . . . . . . . . . 14
4.3 ICN Deployment in LTE Control Plane . . . . . . . . . . . . 17
4.4 ICN Deployment in LTE User Plane . . . . . . . . . . . . . 18
4.4.1 Dual stack ICN Deployments in UE . . . . . . . . . . . 19
4.4.2 Native ICN Deployments in UE . . . . . . . . . . . . . 22
4.5 ICN Deployment in eNodeB . . . . . . . . . . . . . . . . . 23
4.6 ICN Deployment in Packet Core (SGW, PGW) Gateways . . . . . 24
5. Security Considerations . . . . . . . . . . . . . . . . . . . . 26
6. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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7 References . . . . . . . . . . . . . . . . . . . . . . . . . . 29
7.1 Normative References . . . . . . . . . . . . . . . . . . . 29
7.2 Informative References . . . . . . . . . . . . . . . . . . 30
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 31
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1 Introduction
LTE mobile technology is built as all-IP network. It uses IP routing
protocols such as OSPF, ISIS, BGP etc. to establish network routes to
route the data traffic to end user's device. Stickiness of IP address
to a device is the key to get connected to a mobile network and the
same IP address is maintained through the session until the device
gets detached or moves to another network.
One of the key protocols used in 4G and LTE networks is GPRS
Tunneling protocol (GTP). GTP, DIAMETER and other protocols are built
on top of IP. One of the biggest challenges with IP based routing is
that it is not optimized for data transport although it is the most
efficient communication protocol. By native implementation of
Information Centric Networking (ICN) in 3GPP, we can re-architect
mobile network and optimize its design for efficient data transport
by leveraging the caching feature of ICN. ICN also offers an
opportunity to leverage inherent capabilities of multicast,
anchorless mobility management, and authentication. This draft
provides insight into different options for deploying ICN in mobile
networks and how they impact mobile providers and end-users.
1.1 Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
1.2 3GPP Terminology and Concepts
Access Point Name
The Access Point Name (APN) is a Fully Qualified Domain Name
(FQDN) and resolves to a set of gateways in an operator's network.
APN identifies the packet data network (PDN) that a mobile data
user wants to communicate with. In addition to identifying a PDN,
an APN may also be used to define the type of service, QoS and
other logical entities inside GGSN, PGW.
Control Plane
The control plane carries signaling traffic and is responsible for
routing between eNodeB and MME, MME and HSS, MME and SGW, SGW and
PGW etc. Control plane signaling is required to authenticate and
authorize UE and establish mobility session with mobile gateways
(SGW/PGW). Functions of the control plane also include system
configuration and management.
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Dual Address PDN/PDP Type
The dual address Packet Data Network/Packet Data Protocol
(PDN/PDP) Type (IPv4v6) is used in 3GPP context in many cases as a
synonym for dual-stack, i.e. a connection type capable of serving
both IPv4 and IPv6 simultaneously.
eNodeB
The eNodeB is a base station entity that supports the Long-Term
Evolution (LTE) air interface.
Evolved Packet Core
The Evolved Packet Core (EPC) is an evolution of the 3GPP GPRS
system characterized by a higher-data-rate, lower-latency, packet-
optimized system. The EPC comprises some of the sub components of
the EPS core such as Mobility Management Entity (MME), Serving
Gateway (SGW), Packet Data Network Gateway (PDN-GW), and Home
Subscriber Server (HSS).
Evolved Packet System
The Evolved Packet System (EPS) is an evolution of the 3GPP
GPRSsystem characterized by a higher-data-rate, lower-latency,
packet-optimized system that supports multiple Radio Access
Technologies (RATs). The EPS comprises the EPC together with the
Evolved Universal Terrestrial Radio Access (E-UTRA) and the
Evolved Universal Terrestrial Radio Access Network (E-UTRAN).
Evolved UTRAN The Evolved UTRAN (E-UTRAN) is a communications
network, sometimes referred to as 4G, and consists of eNodeBs (4G
base stations). The E-UTRAN allows connectivity between the User
Equipment and the core network.
GPRS Tunnelling Protocol
The GPRS Tunnelling Protocol (GTP) [TS.29060] [TS.29274]
[TS.29281] is a tunnelling protocol defined by 3GPP. It is a
network-based mobility protocol and is similar to Proxy Mobile
IPv6 (PMIPv6). However, GTP also provides functionality beyond
mobility, such as in-band signaling related to Quality of Service
(QoS) and charging, among others.
Gateway GPRS Support Node
The Gateway GPRS Support Node (GGSN) is a gateway function in the
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GPRS and 3G network that provides connectivity to the Internet or
other PDNs. The host attaches to a GGSN identified by an APN
assigned to it by an operator. The GGSN also serves as the
topological anchor for addresses/prefixes assigned to the User
Equipment.
General Packet Radio Service
The General Packet Radio Service (GPRS) is a packet-oriented
mobile data service available to users of the 2G and 3G cellular
communication systems -- the GSM -- specified by 3GPP.
Home Subscriber Server
The Home Subscriber Server (HSS) is a database for a given
subscriber and was introduced in 3GPP Release-5. It is the entity
containing the subscription-related information to support the
network entities actually handling calls/sessions.
Mobility Management Entity
The Mobility Management Entity (MME) is a network element that is
responsible for control-plane functionalities, including
authentication, authorization, bearer management, layer-2
mobility, etc. The MME is essentially the control-plane part of
the SGSN in the GPRS. The user-plane traffic bypasses the MME.
Public Land Mobile Network
The Public Land Mobile Network (PLMN) is a network that is
operated by a single administration. A PLMN (and therefore also an
operator) is identified by the Mobile Country Code (MCC) and the
Mobile Network Code (MNC). Each (telecommunications) operator
providing mobile services has its own PLMN.
Policy and Charging Control
The Policy and Charging Control (PCC) framework is used for QoS
policy and charging control. It has two main functions: flow-
based charging, including online credit control and policy control
(e.g., gating control, QoS control, and QoS signaling). It is
optional to 3GPP EPS but needed if dynamic policy and charging
control by means of PCC rules based on user and services are
desired.
Packet Data Network
The Packet Data Network (PDN) is a packet-based network that
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either belongs to the operator or is an external network such as
the Internet or a corporate intranet. The user eventually accesses
services in one or more PDNs. The operator's packet core networks
are separated from packet data networks either by GGSNs or PDN
Gateways (PGWs).
Serving Gateway
The Serving Gateway (SGW) is a gateway function in the EPS, which
terminates the interface towards the E-UTRAN. The SGW is the
Mobility Anchor point for layer-2 mobility (inter-eNodeB
handovers). For each UE connected with the EPS, at any given
point in time, there is only one SGW. The SGW is essentially the
user-plane part of the GPRS's SGSN.
Packet Data Network Gateway
The Packet Data Network Gateway (PGW) is a gateway function in the
Evolved Packet System (EPS), which provides connectivity to the
Internet or other PDNs. The host attaches to a PGW identified by
an APN assigned to it by an operator. The PGW also serves as the
topological anchor for addresses/prefixes assigned to the User
Equipment.
Packet Data Protocol Context
A Packet Data Protocol (PDP) context is the equivalent of a
virtual connection between the User Equipment (UE) and a PDN using
a specific gateway.
Packet Data Protocol Type
A Packet Data Protocol Type (PDP Type) identifies the used/allowed
protocols within the PDP context. Examples are IPv4, IPv6, and
IPv4v6 (dual-stack).
Serving GPRS Support Node
The Serving GPRS Support Node (SGSN) is a network element that is
located between the radio access network (RAN) and the gateway
(GGSN). A per-UE point-to-point (p2p) tunnel between the GGSN and
SGSN transports the packets between the UE and the gateway.
Terminal Equipment
The Terminal Equipment (TE) is any device/host connected to the
Mobile Terminal (MT) offering services to the user. A TE may
communicate to an MT, for example, over the Point to Point
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Protocol (PPP).
UE, MS, MN, and Mobile
The terms UE (User Equipment), MS (Mobile Station), MN (Mobile
Node), and mobile refer to the devices that are hosts with the
ability to obtain Internet connectivity via a 3GPP network. A MS
is comprised of the Terminal Equipment (TE) and a Mobile Terminal
(MT). The terms UE, MS, MN, and mobile are used interchangeably
within this document.
User Plane
The user plane refers to data traffic and the required bearers for
the data traffic. In practice, IP is the only data traffic
protocol used in the user plane.
2. LTE, 4G Mobile Network
2.1 Network Overview
With the introduction of LTE, mobile networks moved to all-IP
transport for all elements such as eNodeB, MME, SGW/PGW, HSS, PCRF,
routing and switching etc. Although LTE network is data-centric, it
has support for legacy Circuit Switch features like voice and SMS
through transitional CS fallback and flexible IMS deployment
[GRAYSON]. For each mobile device attached to the radio (eNodeB)
there is a separate overlay tunnel (GPRS Tunneling Protocol, GTP)
between eNodeB and Mobile gateways (i.e. SGW, PGW).
The GTP tunnel is used to carry user traffic between gateways and
mobile devices so the data can only be distributed using unicast
mechanism. It is also important to understand the overhead of a GTP
and IPSec protocols because it has impact on the carried user data
traffic. All mobile backhaul traffic is encapsulated using GTP
tunnel, which has overhead of 8 bytes on top of IP and UDP [NGMN].
Additionally, if IPSec is used for security (which is often required
if the Service provider is using a shared backhaul), it adds overhead
based upon IPSec tunneling model (tunnel or transport), and
encryption and authentication header algorithm used. If we factor
Advanced Encryption Standard (AES) encryption with packet size the
overhead can vary significantly [IPSEC2].
When any UE is powered up, it attaches to a mobile network based on
its configuration and subscription. After successful attach
procedure, UE registers with the mobile core network and IPv4 and/or
IPv6 address is assigned. A default bearer is created for each UE and
it is assigned to default Access Point Name (APN).
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+-------+ Diameter +-------+
| HSS |------------| SPR |
+-------+ +-------+
| |
+------+ +------+ S4 | +-------+
| 3G |---| SGSN |----------------|------+ +------| PCRF |
^ |NodeB | | |---------+ +---+ | | +-------+
+-+ | +------+ +------+ S3 | | S6a | |Gxc |
| | | +-------+ | | |Gx
+-+ | +------------------| MME |------+ | | |
UE v | S1MME +-------+ S11 | | | |
+----+-+ +-------+ +-------+
|4G/LTE|------------------------------| SGW |-----| PGW |
|eNodeB| S1U +-------+ +--| |
+------+ | +-------+
+---------------------+ | |
S1U GTP Tunnel traffic | +-------+ | |
S2a GRE Tunnel traffic |S2A | ePDG |-------+ |
S2b GRE Tunnel traffic | +-------+ S2B |SGi
SGi IP traffic | | |
+---------+ +---------+ +-----+
| Trusted | |Untrusted| | CDN |
|non-3GPP | |non-3GPP | +-----+
+---------+ +---------+
| |
+-+ +-+
| | | |
+-+ +-+
UE UE
Figure-1: LTE, 4G Mobile Network Overview
The data delivered to mobile devices is unicast inside GTP tunnel. If
we consider combined impact of GTP, IPSec and unicast traffic, the
data delivery is not efficient. IETF has developed various header
compression algorithms to reduce the overhead associated with IP
packets. Some of techniques are robust header compression (ROHC) and
enhanced compression of the real-time transport protocol (ECRTP) so
that impact of overhead created by GTP, IPsec etc. is reduced to some
extent [BROWER]. For commercial mobile networks, 3GPP has adopted
different mechanisms for header compression to achieve efficiency in
data delivery [TS25.323], and can be used in ICN as well.
2.2 QoS Challenges
During attach procedure, default bearer is created for each UE and it
is assigned to the default Access Point Name (APN). The QoS values
uplink and downlink bandwidth assigned during initial attach are
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minimal. Additional dedicated bearer(s) with enhanced QoS parameters
is established depending on the specific application needs.
While all traffic within a certain bearer gets the same treatment,
QoS parameters supporting these requirements can be very granular in
different bearers. These values vary for the control, management and
user traffic, and depending on the application key parameters, such
as latency, jitter (important for voice and other real-time
applications), packet loss and queuing mechanism (strict priority,
low-latency, fair etc.) can be very different.
Implementation of QoS for mobile networks is done at two stages: at
content prioritization/marking and transport marking, and congestion
management. From the transport perspective, QoS is defined at layer 2
as class of service (CoS) and at layer 3 either as DiffServ code
point (DSCP) or type of service (ToS). The mapping of CoS to DSCP
takes place at layer 2/3 switching and routing elements. 3GPP has
specified QoS Class Identifier (QCI) which represents different types
of content and equivalent mapping to DSCP at transport layer
[TS23.203] [TS23.401]; however, this again requires manual
configuration at different elements and if there is misconfiguration
at any place in the path it will not work properly.
In summary QoS configuration for mobile network for user plane (for
user traffic) and transport in IP based mobile network is complex and
it requires synchronization of parameters among different platforms.
Normally QoS in IP is implemented using DiffServ, which uses hop-by-
hop QoS configuration at each router. Any inconsistency in IP QoS
configuration at routers in the forwarding path can result in poor
subscriber experience (e.g. packet classified as high-priority can go
to lower priority queue). By deploying ICN, we intend to enhance the
subscriber experience using policy based configuration, which can be
associated with the named contents [ICNQoS] at ICN forwarder. Further
investigation is needed to understand how QoS in ICN can be
implemented to meet the IP QoS requirements [RFC4594].
2.3 Data Transport Using IP
The data delivered to mobile devices is unicast inside GTP tunnel
from a eNodeB to a PDN gateway (PGW), as described in 3GPP
specifications [TS23.401]. While the technology exists to address the
issue of possible multicast delivery, there are many difficulties
related to multicast protocol implementation on the RAN side of the
network. Transport networks in the backhaul and core have addressed
the multicast delivery long time ago and have implemented it in most
cases in their multi-purpose integrated transport, but the RAN part
of the network is still lagging behind due to complexities related to
mobility of the clients, handovers, and the fact that the potential
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gain to the Service Providers may not justify the investment. With
that said, the data delivery in the mobility remains greatly unicast.
To ease the burden on the bandwidth of the SGi interface, caching is
introduced in a similar manner as with many Enterprises. In the
mobile networks, whenever possible, a cached data is delivered.
Caching servers are placed at a centralized location, typically in
the Service Provider's Data Center, or in some cases lightly
distributed in the Packet Core locations with the PGW nodes close to
the Internet and IP services access (SGi interface). This is a very
inefficient concept because traffic has to traverse the entire
backhaul path for the data to be delivered to the end-user. Other
issues, such as out-of-order delivery contribute to this complexity
and inefficiency but could be addressed at the IP transport level.
The data delivered to mobile devices is unicast inside a GTP tunnel.
If we consider combined impact of GTP, IPSec and unicast traffic, the
data delivery is not efficient. By deploying ICN, we intend to either
terminate GTP tunnel at the edge by leveraging control and user plane
separation or replace it with the native ICN protocols.
2.4 Virtualizing Mobile Networks
The Mobile packet core deployed in a major service provider network
is either based on dedicated hardware or large capacity x86 platforms
in some cases. With adoption of Mobile Virtual Network Operators
(MVNO), public safety network, and enterprise mobility network, we
need elastic mobile core architecture. By deploying mobile packet
core on a commercially off the shelf (COTS) platform using
virtualized infrastructure (NFVI) framework and end-to-end
orchestration, we can simplify new deployments and provide optimized
total cost of ownership (TCO).
While virtualization is growing and many mobile providers use hybrid
architecture consisting of dedicated and virtualized infrastructures,
the control and data delivery planes are still the same. There is
also work underway to separate control plane and user plane so that
the network can scale better. Virtualized mobile networks and network
slicing with control and user plane separation provide mechanism to
evolve GTP-based architecture to open-flow SDN-based signaling for
LTE and proposed 5G. Some of early architecture work for 5G mobile
technologies provides mechanism for control and user plane separation
and simplifies mobility call flow by introduction of open-flow based
signaling. This has been considered by 3GPP [EPCCUPS] and is also
described in [SDN5G].
3. Data Transport Using ICN
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For mobile devices, the edge connectivity to the network is between
radio and a router or mobile edge computing (MEC) [MECSPEC] element.
MEC has the capability of processing client requests and segregating
control and user traffic at the edge of radio rather than sending all
requests to the mobile gateway.
+----------+
| Content +----------------------------------------+
| Publisher| |
+---+---+--+ |
| | +--+ +--+ +--+ |
| +--->|R1|------------>|R2|---------->|R4| |
| +--+ +--+ +--+ |
| | Cached |
| v content |
| +--+ at R3 |
| +========|R3|---+ |
| # +--+ | |
| # | |
| v v |
| +-+ +-+ |
+---------------| |-------------| |-------------+
+-+ +-+
Consumer-1 Consumer-2
UE UE
===> Content flow from cache
---> Content flow from publisher
Fig. 2. ICN Architecture
MEC transforms radio into an intelligent service edge that is capable
of delivering services directly from the edge of the network, while
providing the best possible performance to the client. MEC can be an
ideal candidate for ICN forwarder in addition to its usual function
of managing mobile termination. In addition to MEC, other transport
elements, such as routers, can work as ICN forwarders.
Data transport using ICN is different compared to IP-based transport.
It evolves the Internet infrastructure by introducing uniquely named
data as a core Internet principle. Communication in ICN takes place
between content provider (producer) and end user (consumer) as
described in figure 2.
Every node in a physical path between a client and a content provider
is called ICN forwarder or router, and it has the ability to route
the request intelligently and also cache the content so that it can
be delivered locally for subsequent request from any other client.
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For mobile network, transport between a client and a content provider
consists of radio network + mobile backhaul and IP core transport +
Mobile Gateways + Internet + content data network (CDN).
In order to understand suitability of ICN for mobile networks, we
will discuss the ICN framework describing protocols architecture and
different types of messages, and then consider how we can use this in
a mobile network for delivering content more efficiently. ICN uses
two types of packets called "interest packet" and "data packet" as
described in figure 3.
+------------------------------------+
Interest | +------+ +------+ +------+ | +-----+
+-+ ---->| CS |---->| PIT |---->| FIB |--------->| CDN |
| | | +------+ +------+ +------+ | +-----+
+-+ | | Add | Drop | | Forward
UE <--------+ Intf v Nack v |
Data | |
+------------------------------------+
+------------------------------------+
+-+ | Forward +------+ | +-----+
| | <-------------------------------------| PIT |<---------| CDN |
+-+ | | Cache +--+---+ | Data +-----+
UE | +--v---+ | |
| | CS | v |
| +------+ Discard |
+------------------------------------+
Fig. 3. ICN Interest, Data Packet and Forwarder
For LTE network, when a mobile device wants to get certain content,
it will send an Interest message to the closest eNodeB. Interest
packet follows the TLV format [CCNxTLV] and contains mandatory fields
such as name of the content and nonce. Name and nonce together
uniquely identify an Interest packet. Nonce is also used to detect
looping Interest messages. Interest packet also contains optional
fields such as selector and guider fields. Selectors provides a
specific filtering action during matching and selection of the name
prefixes. Guiders provides specific set of rules on how the Interest
packet can be processed at the forwarder.
First ICN router will receive Interest packet and perform lookup if
request for such content has come earlier from any other client. If
yes, it is served from the local cache, otherwise request is
forwarded to the next-hop ICN router. Each ICN router maintains three
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data structures, namely Pending Interest Table (PIT), Forwarding
Information Base (FIB), and Content Store (CS). The Interest packet
travels hop-by-hop towards content provider. Once the Interest
reaches the content provider it will return a Data packet containing
information such as content name, signature, signed key and data.
Data packet travels in reverse direction following the same path
taken by the interest packet so routing symmetry is maintained.
Details about algorithms used in PIT, FIB, CS and security trust
models are described in various resources [CCN], here we explained
the concept and its applicability to the LTE network.
4. ICN Deployment in 4G and LTE Networks
4.1 General ICN Deployment Considerations
In LTE/4G mobile networks, both user and control plane traffic have
to be transported from the edge to the mobile packet core via IP
transport. The evolution of existing mobile packet core using CUPS
[TS23.714] enables flexible network deployment and operation, by
distributed deployment and the independent scaling between control
plane and user plane functions - while not affecting the
functionality of the existing nodes subject to this split.
In the CUPS architecture, there is an opportunity to shorten the path
for user plane traffic by deploying offload nodes closer to the edge.
This optimization allows for the introduction of ICN and amplifies
its advantages. This section analyzes the potential impact of ICN on
control and user plane traffic for centralized and disaggregate CUPS
based mobile network architecture.
4.2 ICN Deployment Scenarios
Deployment of ICN provides an opportunity to further optimize the
existing data transport in LTE/4G mobile networks. The various
deployment options that ICN and IP provide are somewhat analogous to
the deployment scenarios when IPv6 was introduced to inter operate
with IPv4, except with ICN the whole IP stack is being replaced. We
have reviewed [RFC6459] and analyzed the impact of ICN on control
plane signaling and user plane data delivery. In general ICN can be
deployed natively replacing IP transport (IPv4 and IPv6) or as an
overlay protocol. Figure 4 describes a modified protocol stack to
support ICN deployment scenarios.
As shown in figure 4, for applications running either in UE or in
content provider system to use the new transport option, we propose a
new transport convergence layer (TCL). This transport convergence
layer helps determine what type of transport (e.g. ICN or IP), as
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well as type of radio interface (e.g. LTE or WiFi or both), is used
to send and receive the traffic based on preference e.g. content
location, content type, content publisher, congestion, cost, quality
of service etc. It helps to configure and decide the type of
connection as well as the overlay mode (ICNoIP or IPoICN) between
application and the protocol stack (IP or ICN) to be used.
+----------------+ +-----------------+
| ICN App (new) | |IP App (existing)|
+---------+------+ +-------+---------+
| |
+---------+----------------+---------+
| Transport Convergence Layer (new) |
+------+---------------------+-------+
| |
+------+------+ +------+-------+
|ICN function | | IP function |
| (New) | | (Existing) |
+------+------+ +------+-------+
| |
(```). (```).
( ICN '`. ( IP '`.
( Cloud ) ( Cloud )
` __..'+' ` __..'+'
Fig. 4. IP/ICN Convergence and Deployment Scenarios
TCL can use a number of mechanisms for the selection of transport. It
can use a per application configuration through a management
interface, possibly even a user-facing setting realized through a
user interface, similar to those used today that select cellular over
WiFi being used for selected applications. In another option, it
might use a software API, which an adapted IP application could use
to specify e.g. an ICN transport for obtaining its benefits.
Another potential application of TCL is in implementation of network
slicing, where it can have a slice management capability locally or
it can interface to an external slice manager through an API [GALIS].
This solution can enable network slicing for IP and ICN transport
selection from the UE itself. The TCL could apply slice settings to
direct certain traffic (or applications) over one slice and others
over another slice, determined by some form of 'slicing policy'.
Slicing policy can be obtained externally from slice manager or
configured locally on UE.
From the perspective of the applications either on UE or content
provider, four different options are possible for the deployment of
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ICN natively and/or with IP.
1. IP over IP
In this scenario UE uses applications tightly integrated with
the existing IP transport infrastructure. In this option, the
TCL has no additional function since the packets are directly
forwarded using IP protocol stack, which in turn sends the
packets over the IP transport.
2. ICN over ICN
Similar to case 1 above, ICN applications tightly integrate
with the ICN transport infrastructure. The TCL has no
additional responsibility since the packets are directly
forwarded using ICN protocol stack, which in turn sends the
packets over the ICN transport.
3. ICN over IP (ICNoIP)
In ICN over IP scenario, the underlying IP transport
infrastructure is not impacted (i.e. ICN is implemented, as an
IP overlay, between user equipment (UE) and content provider).
IP routing is used from Radio Access Network (eNodeB) to mobile
backhaul, IP core and Mobile Gateway (SGW/PGW). UE attaches to
Mobile Gateway (SGW/PGW) using IP address. Also, the data
transport between Mobile Gateway (SGW/PGW) and content
publisher uses IP. Content provider is capable of serving
content either using IP or ICN, based on UE request.
An alternative approach to implement ICN over IP is provided in
Hybrid ICN [HICN], which implements ICN over IP by mapping of
ICN names to the IPv4/IPv6 addresses.
Detailed deployment of use cases is described in section 4.4.
Application conveys the preference to the TCL, which in turn
sends the ICN data packets using the IP transport.
4. IP over ICN (IPoICN)
H2020 project [H2020] provides an architectural framework for
deployment of IP as an overlay over ICN protocol [IPICN].
Implementing IP services over ICN provides an opportunity
leveraging benefit of ICN in the transport infrastructure and
there is no impact on end devices (UE and access network) as
they continue to use IP. IPoICN however, will require an inter-
working function (IWF/Border Gateway) to translate various
transport primitives such as transport of tunnel mode. IWF
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function will provide a mechanism for protocol translation
between IPoICN and native IP deployment for mobile network.
After reviewing [IPICN], we understand and interpret that ICN
is implemented in the transport natively; however, IP is
implemented in UE, eNodeB, and Mobile gateway (SGW/PGW), which
is also called as network attach point (NAP).
4.3 ICN Deployment in LTE Control Plane
In this section we analyze signaling messages which are required for
different procedures, such as attach, handover, tracking area update
etc. The goal of analysis is to see if there is any benefit to
replace IP-based protocols with ICN for LTE signaling in the current
architecture. It is important to understand the concept of point of
attachment (POA). When UE connects to a network it has at least three
POAs:
1. eNodeb managing location or physical POA
2. Authentication and Authorization (MME, HSS) managing identity
or authentication POA
3. Mobile Gateways (SGW, PGW) managing logical or session
management POA.
In current architecture IP transport is used for all the messages
associated with Control Plane for mobility and session management. IP
is embedded very deeply into these messages and TLV carrying
additional attributes as a layer 3 transport . Physical POA in eNodeB
handles both mobility and session management for any UE attached to
4G, LTE network. The number of mobility management messages between
different nodes in an LTE network per signaling procedure are given
below in figure 5.
Normally two types of UE devices attach to LTE network: SIM based
(need 3GPP mobility protocol for authentication) or non-SIM based
(which connect to WiFi network), and authentication is required for
both of these device types. For non-SIM based devices, AAA is used
for authentication. We do not propose to change UE authentication
procedures for user data transport using ICN, or any other mobility
management messaging. A separate study would be required to analyze
impact of ICN on mobility management messages structures and flows.
We are merely analyzing the viability of implementing ICN as a
transport for Control plane messages.
It is important to note that even if MME and HSS do not support ICN
transport, they still need to support UE capable of dual stack or
native ICN. When UE initiates attach request using the identity as
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ICN, MME must be able to parse that message and create a session. MME
forwards UE authentication to HSS so HSS must be able to authenticate
an ICN capable UE and authorize create session [TS23.401].
+---------------------------+-------+-------+-------+-------+------+
| LTE Signaling Procedures | MME | HSS | SGW | PGW | PCRF |
+------------------------------------------------------------------+
| Attach | 10 | 2 | 3 | 2 | 1 |
| Additional default bearer | 4 | 0 | 3 | 2 | 1 |
| Dedicated bearer | 2 | 0 | 2 | 2 | 1 |
| Idle-to-connect | 3 | 0 | 1 | 0 | 0 |
| Connect-to-Idle | 3 | 0 | 1 | 0 | 0 |
| X2 handover | 2 | 0 | 1 | 0 | 0 |
| S1 handover | 8 | 0 | 3 | 0 | 0 |
| Tracking area update | 2 | 0 | 0 | 0 | 0 |
| Total | 34 | 2 | 14 | 6 | 3 |
+---------------------------+-------+-------+-------+-------+------+
Fig. 5. Signaling Messages in LTE Gateways
Anchorless mobility [ALM] has made some important comments on how
mobility management is done in ICN. Author comments about handling
mobility without having a dependency on the core network function
e.g. MME. However, location update to the core network would still be
required to support some of the legal compliance requirements such as
lawful intercept and emergency services.
The main advantage of ICN is in caching and reusing the content,
which does not apply to the transactional signaling exchange. After
analyzing LTE signaling call flows [TS23.401] and messages inter-
dependencies [Fig 4], our recommendation is that it is not beneficial
to deploy ICN for control plane and mobility management functions.
4.4 ICN Deployment in LTE User Plane
We will consider figure 1 to discuss different mechanisms to deploy
ICN in mobile networks. In section 4.2 we discussed generic
deployment scenarios of ICN. In this section, we shall see the
specific use cases of native ICN deployment in LTE user plane. We
consider the following options:
1. Dual stack ICN deployment in UE
2. Native ICN Deployments in UE
3. ICN Deployment in eNodeB
4. ICN Deployment in mobile gateways (SGW/PGW)
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4.4.1 Dual stack ICN Deployments in UE
The control and user plane communications in LTE, 4G mobile networks
are specified in 3GPP documents [TS23.323] [TS23.203] [TS23.401]. It
is important to understand that UE can be either consumer (receiving
content) or publisher (pushing content for other clients). The
protocol stack inside mobile device (UE) is complex as it has to
support multiple radio connectivity access to eNodeB(s).
Figure 6 provides high level description of a protocol stack, where
IP is defined at two layers: (1) at user plane communication, (2)
Transport layer. User plane communication takes place between Packet
Data Convergence Protocol (PDCP) and Application layer, whereas
transport layer is at GTP protocol stack.
+--------+ +--------+
| App | | CDN |
+--------+ +--------+ +--------+
|Transp. | | | | |Transp. | | |Transp. |
|Converg.| |..............|...............|.|Converge|.|.|Converge|
+--------+ | | | +--------+ | +--------+
| |.|..............|...............|.| |.|.| |
| ICN/IP | | | | | ICN/IP | | | ICN/IP|
| | | | | | | | | |
+--------+ | +----+-----+ | +-----+-----+ | +-----+--+ | +--------+
| |.|.| | |.|.| | |.|.| | | | | |
| PDCP | | |PDCP|GTP-U| | |GTP-U|GTP-U| | |GTP-U| | | | L2 |
+--------+ | +----------+ | +-----------+ | +-----+ | | | |
| RLC |.|.|RLC | UDP |.|.| UDP | UDP |.|.|UDP |L2|.|.| |
+--------+ | +----------+ | +-----------+ | +-----+ | | | |
| MAC |.|.| MAC| L2 |.|.| L2 | L2 |.|.| L2 | | | | |
+--------+ | +----------+ | +-----------+ | +--------+ | +--------+
| L1 |.|.| L1 | L1 |.|.| L1 | L1 |.|.| L1 |L1|.|.| L1 |
+--------+ | +----+-----+ | +-----+-----+ | +-----+--+ | +--------+
UE | BS(enodeB) | SGW | PGW |
Uu S1U S5/S8 SGi
Fig. 6. Dual stack ICN Deployment in UE
The protocol interactions and impact of supporting tunneling of ICN
packet into IP or to support ICN natively are described in figure 6
and figure 7 respectively.
The protocols and software stack used inside LTE capable UE support
both 3G and LTE software interworking and handover. Latest 3GPP
Rel.13 onward specification describes the use of IP and non-IP
protocols to establish logical/session connectivity. We intend to
leverage the non-IP protocol based mechanism to deploy ICN protocol
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stack in UE as well as in eNodeB and mobile gateways (SGW, PGW).
+----------------+ +-----------------+
| ICN App (new) | |IP App (existing)|
+---------+------+ +-------+---------+
| |
+---------+----------------+---------+
| Transport Convergence Layer (new) |
+------+---------------------+-------+
| |
+------+------+ +------+-------+
|ICN function | | IP function |
| (New) | | (Existing) |
+------+------+ +------+-------+
| |
+------+---------------------+-------+
| PDCP (updated to support ICN) |
+-----------------+------------------+
|
+-----------------+------------------+
| RLC (Existing) |
+-----------------+------------------+
|
+-----------------+------------------+
| MAC Layer (Existing) |
+-----------------+------------------+
|
+-----------------+------------------+
| Physical L1 (Existing) |
+------------------------------------+
Fig. 7. Dual stack ICN protocol interactions
1. Existing application layer can be modified to provide options
for new ICN based application and existing IP based
applications. UE can continue to support existing IP based
applications or host new applications developed either to
support native ICN as transport, ICNoIP or IPoICN based
transport. Application layer has the option of selecting either
ICN or IP transport layer as well as radio interface to send
and receive data traffic.
Our proposal is to provide a common Application Programming
Interface (API) to the application developers such that there
is no impact on the application development when they choose
either ICN or IP transport for exchanging the traffic with the
network. As mentioned in section 4.2, the transport convergence
layer (TCL) function handles the interaction of application
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with the multiple transport options.
2. The transport convergence layer helps determine what type of
transport (e.g. ICN or IP) as well as type of radio interface
(e.g. LTE or WiFi or both), is used to send and receive the
traffic. Application layer can make the decision to select a
specific transport based on preference e.g. content location,
content type, content publisher, congestion, cost, quality of
service etc. There can be an Application Programming Interface
(API) to exchange parameters required for transport selection.
The southbound interactions of Transport Convergence Layer
(TCL) will be either to IP or ICN at the network layer.
3. ICN function (forwarder) is introduced in parallel to the
existing IP layer. ICN forwarder contains functional
capabilities to forward ICN packets, e.g. Interest packet to
eNodeB or response "data packet" from eNodeB to the
application.
4. For dual stack scenario, when UE is not supporting ICN at
transport layer, we use IP underlay to transport ICN packets.
ICN function will use IP interface to send Interest and Data
packets for fetching or sending data using ICN protocol
function. This interface will use ICN overlay over IP using any
overlay tunneling mechanism.
5. To support ICN at network layer in UE, PDCP layer has to be
aware of ICN capabilities and parameters. PDCP is located in
the Radio Protocol Stack in the LTE Air interface, between IP
(Network layer) and Radio Link Control Layer (RLC). PDCP
performs following functions [TS36.323]:
a) Data transport by listening to upper layer, formatting and
pushing down to Radio Link Layer (RLC)
b) Header compression and decompression using ROHC (Robust
Header Compression)
c) Security protections such as ciphering, deciphering and
integrity protection
d) Radio layer messages associated with sequencing, packet drop
detection and re-transmission etc.
6. No changes are required for lower layer such as RLC, MAC and
Physical (L1) because they are not IP aware.
One key point to understand in this scenario is that ICN is deployed
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as an overlay on top of IP.
4.4.2 Native ICN Deployments in UE
We propose to implement ICN natively in UE by modifying PDCP layer in
3GPP protocols. Figure 8 provides a high-level protocol stack
description where ICN is used at two different layers:
1. at user plane communication
2. at transport layer
User plane communication takes place between PDCP and application
layer, whereas transport layer is a substitute of GTP protocol.
Removal of GTP protocol stack is significant change in mobile
architecture because GTP is used not just for routing but for
mobility management functions such as billing, mediation, policy
enforcement etc.
+--------+ +--------+
| App | | CDN |
+--------+ +--------+
|Transp. | | | | | |Transp. |
|Converge|.|..............|..............|..............|.|COnverge|
+--------+ | | | | +--------+
| |.|..............|..............|..............|.| |
| ICN/IP | | | | | | |
| | | | | | | |
+--------+ | +----+-----+ | +----------+ | +----------+ | | ICN/IP |
| |.|.| | | | | | | | | | | |
| PDCP | | |PDCP| ICN |.|.| ICN |.|.| ICN |.|.| |
+--------+ | +----+ | | | | | | | | | |
| RLC |.|.|RLC | | | | | | | | | | |
+--------+ | +----------+ | +----------+ | +----------+ | +--------+
| MAC |.|.| MAC| L2 |.|.| L2 |.|.| L2 |.|.| L2 |
+--------+ | +----------+ | +----------+ | +----------+ | +--------+
| L1 |.|.| L1 | L1 |.|.| L1 |.|.| L1 |.|.| L1 |
+--------+ | +----+-----+ | +----------+ | +----------+ | +--------+
UE | BS(enodeB) | SGW | PGW |
Uu S1u S5/S8 SGi
Fig. 8. Native ICN Deployment in UE
If we implement ICN natively in UE, communication between UE and
eNodeB will change and also we will not need to tunnel user plane
traffic from eNodeB to mobile packet core (SGW, PGW) using GTP
tunnel.
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For native ICN deployment, Application is configured to use ICN
forwarder so there is no need for Transport Convergence. Also to
support ICN at network layer in UE, we need to modify existing PDCP
layer. PDCP layer has to be aware of ICN capabilities and parameters.
Native implementation will also provide opportunities to develop new
use cases leveraging ICN capabilities such as seamless mobility, UE
to UE content delivery using radio network without interactions with
mobile gateways, etc.
4.5 ICN Deployment in eNodeB
eNodeB is physical point of attachment for UE, where radio protocols
are converted into IP transport protocol as depicted in figure 7 and
figure 8 for dual stack/overlay and native ICN respectively. When UE
performs attach procedures, it is assigned an identity either as IP,
dual stack (IP and ICN), or ICN. UE can initiate data traffic using
any of three different options:
1. Native IP (IPv4 or IPv6)
2. Native ICN
3. Dual stack IP (IPv4/IPv6) or ICN
UE encapsulates user data transport request into PDCP layer and sends
the information on air interface to eNodeB. eNodeB receives the
information and using PDCP [TS 36.323], de-encapsulates air-interface
messages and converts them to forward to core mobile gateways (SGW,
PGW). In order to support ICN natively in eNodeB, it is proposed to
provide transport convergence layer (TCL) capabilities in eNodeB
(similar as provided in UE), which provides following functions:
1. It decides the forwarding strategy for user data request coming
from UE. The strategy can make decision based on preference
indicated by the application such as congestion, cost, quality
of service, etc.
2. eNodeB to provide open Application Programming Interface (API)
to external management systems, to provide capability to eNodeB
to program the forwarding strategies.
3. eNodeB shall be upgraded to support three different types of
transport: IP, ICN, and dual stack IP+ICN towards mobile
gateways, as depicted in figure 9. It is also recommended to
deploy IP and/or ICN forwarding capabilities into eNodeB for
efficient transfer of data between eNodeB and mobile gateways.
There can be four choices for forwarding data request towards
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mobile gateways:
a) Assuming eNodeB is IP-enabled and UE requests IP transfer,
eNodeB forwards data over IP.
b) Assuming eNodeB is ICN-enabled and UE requests ICN transfer,
eNodeB forwards data over ICN.
c) Assuming eNodeB is IP-enabled and UE requests ICN, eNodeB
overlays ICN on IP and forwards the user plane traffic over
IP.
d) Assuming eNodeB is ICN-enabled and UE requests IP, eNodeB
overlays IP on ICN and forwards the user plane traffic over
ICN [IPoICN].
+---------------+ |
| UE request | | ICN +---------+
+---> | content using |--+--- transport -->| |
| |ICN protocol | | | |
| +---------------+ | | |
| | | |
| +---------------+ | | |
+-+ | | UE request | | IP |To mobile|
| |---+---> | content using |--+--- transport -->| GW |
+-+ | | IP protocol | | |(SGW,PGW)|
UE | +---------------+ | | |
| | | |
| +---------------+ | | |
| | UE request | | Dual stack | |
+---> | content using |--+--- IP+ICN -->| |
|IP/ICN protocol| | transport +---------+
+---------------+ |
eNodeB S1u
Fig. 9. Native ICN Deployment in eNodeB
4.6 ICN Deployment in Packet Core (SGW, PGW) Gateways
Mobile gateways a.k.a. Evolved Packet Core (EPC) include SGW, PGW,
which perform session management for UE from the initial attach to
disconnection. When UE is powered on, it performs NAS signaling and
after successful authentication it attaches to PGW. PGW is an
anchoring point for UE and responsible for service creations,
authorization, maintenance etc. Entire functionality is managed using
IP address(es) for UE.
In order to implement ICN in EPC, the following functions are needed.
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1. Insert ICN function at session management layer as additional
functionality with IP stack. Session management layer is used
for performing attach procedures and assigning logical identity
to user. After successful authentication by HSS, MME sends
create session request (CSR) to SGW and SGW to PGW.
2. When MME sends Create Session Request message (step 12 in
[TS23.401]) to SGW or PGW, it contains Protocol Configuration
Option Information Element (PCO IE) containing UE capabilities.
We can use PCO IE to carry ICN related capabilities information
from UE to PGW. This information is received from UE during the
initial attach request in MME. Details of available TLV, which
can be used for ICN are given in subsequent sections. UE can
support either native IP, or ICN+IP, or native ICN. IP is
referred to as both IPv4 and IPv6 protocols.
3. For ICN+IP capable UE, PGW assigns the UE both IP address and
ICN identity. UE selects either of the identities during the
initial attach procedures and registers with network for
session management. For ICN-capable UE it will provide only ICN
attachment. For native IP-capable UE there is no change.
4. In order to support ICN-capable attach procedures and use ICN
for user plane traffic, PGW needs to have full ICN protocol
stack functionalities. Typical ICN capabilities include
functions such as content store (CS), Pending Interest Table
(PIT), Forwarding Information Base (FIB) capabilities etc. If
UE requests ICN in PCO IE, then PGW registers UE with ICN
names. For ICN forwarding, PGW caches content locally using CS
functionality.
5. Protocol configuration options information elements described
in [TS24.008] (see Figure 10.5.136 on page 598) and [TS24.008]
(see Table 10.5.154 on page 599) provide details for different
fields.
- Octet 3 (configuration protocols defines PDN types) which
contains details about IPv4, IPv6, both or ICN.
- Any combination of Octet 4 to Z can be used to provide
additional information related to ICN capability. It is most
important that PCO IE parameters are matched between UE and
mobile gateways (SGW, PGW) so that they can be interpreted
properly and UE can attach successfully.
6. Deployment of ICN functionalities in SGW and PGW should be
matched with UE and eNodeB because they will exchange ICN
protocols and parameters.
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7. Mobile gateways SGW, PGW will also need ICN forwarding and
caching capability.
8. The transport between PGW and CDN provider can be either IP or
ICN. When UE is attached to PGW with ICN identity and
communicates with an ICN-enabled CDN provider, it will use ICN
primitives to fetch the data. On other hand, for an UE attached
with an ICN identity, if PGW has to communicate with an IP-
enabled CDN provider, it will have to use an ICN-IP
interworking gateway to perform conversion between ICN and IP
primitives for data retrieval. Further study is required to
understand how this ICN to IP (and vice versa) interworking
gateway would function.
5. Security Considerations
To ensure only authenticated UEs are connected to the network, LTE
mobile network implements various security mechanisms. From
perspective of ICN deployment in user plane, it needs to take care of
the following security aspects:
1. UE authentication and authorization
2. Radio or air interface security
3. Denial of service attacks on mobile gateway, services
4. Content positioning either in transport or servers
5. Content cache pollution attacks
6. Secure naming, routing, and forwarding
7. Application security
Security over the LTE air interface is provided through cryptographic
technique. When UE is powered up, it performs key exchange between
UE's USIM and HSS/Authentication Center using NAS messages including
ciphering and integrity protections between UE and MME. Details of
secure UE authentication, key exchange, ciphering and integrity
protections messages are given in 3GPP call flow [TS23.401].
LTE is an all-IP network and uses IP transport in its mobile backhaul
(e.g. between eNodeB and core network). In case of provider owned
backhaul, it may not implement security mechanisms; however, they are
necessary in case it uses shared or a leased network. The native IP
transport continues to leverage security mechanism such as Internet
key exchange (IKE) and the IP security protocol (IPsec). More details
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of mobile backhaul security are provided in 3GPP network security
[TS33.310] and [TS33.320]. When mobile backhaul is upgraded to
support dual stack (IP+ICN) or native ICN, it is required to
implement security techniques which are deployed in mobile backhaul.
When ICN forwarding is enabled on mobile transport routers, we need
to deploy security practices based on RFC7476 and RFC7927.
Some of the key functions supported by LTE mobile gateway (SGW, PGW)
are content based billing, deep packet inspection (DPI), and lawful
intercept (LI). For ICN-based user plane traffic, it is required to
integrate ICN security for session between UE and gateway; however,
in ICN network, since only consumers who are in possession of
decryption keys can access the content, some of the services provided
by mobile gateways mentioned above may not work. Further research in
this area is needed.
6. Summary
In this draft, we have discussed complexities of LTE network and key
dependencies for deploying ICN in user plane data transport.
Different deployment options described cover aspects such as inter-
operability and multi-technology, which is a reality for any service
provider. We are currently evaluating the ICN deployment options,
described in section 4, using LTE gateway software and ICN simulator.
One can deploy ICN for data transport in user plane either as an
overlay, dual stack (IP + ICN) or natively (by integrating ICN with
CDN, eNodeB, SGW, PGW and transport network etc.). It is important to
understand that for above discussed deployment scenarios, additional
study is required for lawful interception, billing/mediation, network
slicing, and provisioning APIs.
Based on our study of control plane signaling it is not beneficial to
deploy ICN with existing protocols unless further changes are
introduced in the control protocol stack itself. As mentioned in
[TS23.501], 5G network architecture proposes simplification of
control plane messages and can be a candidate for use of ICN.
As a starting step towards ICN user plane deployment, it is
recommended to incorporate protocol changes in UE, eNodeB, SGW/PGW
for data transport. ICN has inherent capabilities for mobility and
content caching, which can improve the efficiency of data transport
for unicast and multicast delivery.
Mobile Edge Computing (MEC) [CHENG] provides capabilities to deploy
functionalities such as Content Delivery Network (CDN) caching and
mobile user plane functions (UPF) [TS23.501]. Recent research for
delivering real-time video content using ICN has also been proven to
be efficient [NDNRTC] and can be used towards realizing the benefits
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of ICN deployment in eNodeB, MEC, mobile gateways (SGW, PGW) and CDN.
The key aspect for ICN is in its seamless integration in LTE and 5G
networks with tangible benefits so that we can optimize content
delivery using simple and scalable architecture. Authors will
continue to explore how ICN forwarding in MEC could be used in
efficient data delivery from mobile edge.
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7 References
7.1 Normative References
[GRAYSON] Grayson M, Shatzkamer K, Wainner S.; Cisco Press book "IP
Design for Mobile Networks" by. page 108-112.
[IPSEC1] Cisco IPSec overhead calculator tool
<https://cway.cisco.com/tools/ipsec-overhead-calc/ipsec-
overhead-calc.html>.
[IPSEC2] IPSec Bandwidth Overhead Using AES
<http://packetpushers.net/ipsec-bandwidth-overhead-using-
aes/>.
[BROWER] Brower, E.; Jeffress, L.; Pezeshki, J.; Jasani, R.;
Ertekin, E. "Integrating Header Compression with IPsec",
Military Communications Conference, 2006. MILCOM 2006.
IEEE, On page(s): 1 - 6.
[TS25.323] 3GPP TS25.323 Rel. 14 (2017-03) Packet Data Convergence
Protocol (PDCP) specification.
[TS23.501] 3GPP TS23.501 Rel. 15 (2017-06) System Architecture for
the 5G System.
[TS23.203] 3GPP TS23.203 Rel. 14 (2017-03) Policy and charging
control and QoS architecture
[TS23.401] 3GPP TS23.401 Rel. 14 (2017-03) E-UTRAN Access procedures
architecture
[TS33.310] 3GPP TS33.310 Rel. 14 (2016-12) LTE Network Domain
Security (NDS); Authentication Framework (AF)
[TS33.320] 3GPP TS33.320 Rel. 14 (2016-12) Security of Home Node B
(HNB) / Home evolved Node B (HeNB)
[TS24.008] 3GPP TS24.008 Rel. 14 (2017-06) Mobile radio interface
Layer 3 specification.
[TS23.501] 3GPP TS23.501 Rel. 14 (2017-06) System Architecture for
the 5G System
[TS23.214] 3GPP TS23.214 Rel. 14 (2017-06) Architecture enhancements
for control and user plane separation of EPC nodes
[TS36.323] 3GPP TS36.323 Rel. 14 (2017-06) Evolved Universal
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Terrestrial Radio Access (E-UTRA); Packet Data Convergence
Protocol (PDCP) specification
[TS23.714] 3GPP TS23.714 Rel. 14 (2016-06) Technical Specification
Group Services and System Aspects: Study on control and
user plane separation of EPC nodes
[RFC7476] Information-Centric Networking: Baseline Scenarios
[RFC7927] Information-Centric Networking (ICN) Research Challenges
[RFC6459] IPv6 in 3GPP Evolved Packet System (EPS)
7.2 Informative References
[RFC2119] Key words for use in RFCs to Indicate Requirement Levels
<https://www.ietf.org/rfc/rfc2119.txt>
[MECSPEC] European Telecommunication Standards Institute (ETSI) MEC
specification ETSI-GS-MEC-IEG-001 V1.1.1 (2015-11).
[NDNTLV] NDN Interest Packet Format Specification 0.2-2.
<https://named-data. net/doc/ndn-tlv/interest.html>
[CCNxTLV] CCNx Messages in TLV Format
<https://datatracker.ietf.org/doc/draft-irtf-icnrg-
ccnxmessages/>
[NDNPUB] Named Data Networking <http://named-
data.net/publications/>.
[CCN] Content Centric Networking <http://www.ccnx.org and
http://blogs.parc.com/ccnx/documentation-guide/>.
[NDN] Lixia Z., Lan W. et al. SIGCOMM Named Data Networking
[ALM] J. Aug'e, G. Carofiglio et al. "Anchor-less producer
mobility in icn," in Proceedings of the 2Nd ACM Conference
on Information-Centric Networking, ACM-ICN '15, pp. 189-
190, ACM, 2015.
[VNIIDX] Cisco Visual Networking Index (VNI) dated 16 Feb 2016,
<http://www.cisco.com/c/en/us/solutions/service-
provider/visual-networking-index-vni/index.html>.
[NDNRTC] Peter Gusev,Zhehao Wang, Jeff Burke, Lixia Zhang et. All,
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IEICE Trans Communication, RealtimeStreaming Data Delivery
over Named Data Networking, Vol E99-B, No.5 May 2016.
[CHENG] Chengchao L., F. Richard Yu, Information-centric network
fucntion virtualization over 5G mobile wireless networks,
IEEE network (Volume:29, Issue:3), page 68-74, 01 June
2015.
[NGMN] Backhaul Provisioning for LTE-Advanced & Small Cells
<https://www.ngmn.org/uploads/media/150929_NGMN_P-
SmallCells_Backhaul_for_LTE-Advanced_and_Small_Cells.pdf>
[IPoICN] IP Over ICN - The Better IP?
<http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7194109>
[HICN] Cisco Hybrid ICN <http://blogs.cisco.com/sp/cisco-
announces-important-steps-toward-adoption-of-information-
centric-networking>
[GALIS] Autonomic Slice Networking-Requirements and Reference
Model <https://www.ietf.org/id/draft-galis-anima-
autonomic-slice-networking-02.txt>
[EPCCUPS] Control and User Plane Separation of EPC nodes (CUPS).
<http://www.3gpp.org/news-events/3gpp-news/1882-cups>
[SDN5G] Software-defined networking for low-latency 5G core
network. <http://ieeexplore.ieee.org/document/7496561/>
[ICNQoS] Quality of Service in an Information-Centric Network.
<http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=7037079>
[RFC4594] Configuration Guidelines for DiffServ Service Classes
Authors' Addresses
Prakash Suthar
9501 Technology Blvd.
Rosemont, Illinois 60018
EMail: psuthar@cisco.com
Milan Stolic
9501 Technology Blvd.
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Rosemont, Illinois 60018
EMail: mistolic@cisco.com
Anil Jangam
3625 Cisco Way
San Jose, CA 95134
USA
Email: anjangam@cisco.com
Dirk Trossen
InterDigital Inc.
64 Great Eastern Street, 1st Floor
London EC2A 3QR
United Kingdom
Email: Dirk.Trossen@InterDigital.com
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