Internet DRAFT - draft-sheng-idr-advertising-saas-path-performance
draft-sheng-idr-advertising-saas-path-performance
IDR C. Sheng
Internet-Draft H. Shi, Ed.
Intended status: Standards Track Huawei
Expires: 25 April 2024 L. Dunbar
Futurewei
23 October 2023
Advertising SaaS Path Performance Metrics using BGP
draft-sheng-idr-advertising-saas-path-performance-00
Abstract
This document extends BGP to advertise the SaaS path performance
metrics from the gateway sites to branch sites. The user can access
SaaS applications through the DIA (Direct Internet Access) link at
the branch site or through the DIA link at the gateway site, or use
the DIA link of a gateway site for redundancy. This approach will
improve the SaaS access experience for end-users.
Status of This Memo
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This Internet-Draft will expire on 25 April 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Provisions Relating to IETF Documents (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4
3. Dynamically Select the Best Path . . . . . . . . . . . . . . 4
4. The SaaS Path Performance Route . . . . . . . . . . . . . . . 6
4.1. The SaaS Path Performance Route Encoding . . . . . . . . 6
4.2. The SaaS Path Performance Metrics Encoding . . . . . . . 8
4.2.1. The SaaS Path Delay Sub-TLV format . . . . . . . . . 8
4.2.2. The SaaS Path Loss Sub-TLV format . . . . . . . . . . 9
4.2.3. The SaaS Path Jitter Sub-TLV format . . . . . . . . . 9
4.2.4. The SaaS Path Bandwidth Sub-TLV format . . . . . . . 9
4.2.5. The SaaS Path Status Sub-TLV format . . . . . . . . . 10
4.2.6. The SaaS Path QoS Sub-TLV format . . . . . . . . . . 11
4.2.7. The SaaS Application Name Sub-TLV format . . . . . . 11
4.2.8. The SaaS Application Domain Name Sub-TLV format . . . 11
5. Security Considerations . . . . . . . . . . . . . . . . . . . 12
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
7. Normative References . . . . . . . . . . . . . . . . . . . . 12
Appendix A. Contributors . . . . . . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction
With the continuous cloudification of enterprise IT architectures and
widespread use of public clouds, more and more enterprises are
turning their infrastructures (such as enterprise data centers) to
cloudification, abandoning traditional closed IT architectures and
using open network architectures. To further achieve this goal,
enterprises' mission-critical applications, such as office,
production ERP systems, and sales systems, are migrated to the cloud.
In this case, enterprises increasingly rely on software as a service
(SaaS) provided by application service providers and prefer to access
mission-critical applications from the cloud over the Internet.
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Accessing SaaS applications like SalesForce, SharePoint, Dropbox and
Office 365 over congested public networks can be unreliable and slow,
due to heavy traffic, packet loss, and fluctuating latencies.
Application slowness results in poor end-user experience.
This document provides a way to improve the SaaS access experience.
As shown in the Figure 1, user can access SaaS applications through
the DIA (Direct Internet Access) link at the branch site or through
the DIA link at the gateway site. The GWs at the gateway site
normally have stronger capabilities and will provide SaaS access
services for branch sites. The CPE at the branch site need to choose
the best path for each SaaS application. The performance of the path
between gateway and SaaS application needs to be advertised to CPE.
This document extends BGP to advertise the SaaS path performance
metrics.
(^^^^^^^^^^^^^^^^^^^^^^^)
( SaaS Apps )
( +----+ +----+ +----+ )
( |App1| |App2| |App3| )
( +----+ +----+ +----+ )
(^^^^^^^^^^^^^^^^^^^^^^^)
| | |
| | |
| .|----|
| ( | |)
.-|( | | )--.
+-----(--+Internet/MPLS )
/ '--( | | )--'
/ ( | \)
/ '|----'\
+ | +----|-----------+
DIA | Link \ | +--|--+ |
| +-------------\--| GW2 | |
| / SD-WAN Tunnel \ +-----+ |
| / |\ Hub Site|
+----+ +-|/-+ SD-WAN Tunnel | \-----+ |
|User|--|CPE1|-----------------| GW1 | |
+----+ +----+ | +-----+ |
Branch Site +----------------+
Figure 1: SaaS Application Path Performance Optimization Scenario
2. Terminology
In addition to terms defined in [I-D.ietf-idr-sdwan-edge-discovery],
this document uses following terms:
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* DIA: Direct Internet Access
* FQDN: Fully Qualified Domain Name
* QoS: Quality of Service
* SaaS: Software-as-a-Service
2.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Dynamically Select the Best Path
This section uses the scenario shown in Figure 1 as an example to
describe how to implement the SaaS Path Optimization solution.
Both the Branch and GW routers initiate periodic probes to target
SaaS applications. The GW routers advertise the probe result to the
Branch routers. The following figure shows the SaaS Path Performance
Metrics table on the CPE1. Note that in this example, CPE1, GW1, and
GW2 have multiple paths for accessing App1, 2 paths are listed for
each device. The access to App2 and App3 is similar, only one entry
is listed for the purpose of simplifying the description.
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+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|Name|ID|Path |Path Out Intf |O_QoS|Status| L | D | J | B |F_QoS|
| | |Index|(# Remote) | | | | | | | |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I11 | GE 0/0/1.1 | 75 | Good | 1|150| 40|B01| 75 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I12 | GE 0/0/1.1 | 80 | Good | 1|160| 40|B01| 80 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I13 |# GW1-System IP| 85 | Good | 0|100| 40|B11| 83 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I14 |# GW1-System IP| 85 | Good | 0|100| 40|B12| 81 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I15 |# GW2-System IP| 90 | Best | 0| 80| 20|B13| 82 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App1|10| I16 |# GW2-System IP| 90 | Best | 0| 80| 20|B14| 88 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App2|20| I02 | GE 0/0/1.1 | 40 |Issue | 5|180|101|B02| 40 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App2|20| I21 |# GW1-System IP| 80 | Good | 1|100| 70|B21| 75 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App2|20| I22 |# GW2-System IP| 60 | Acct | 3|160| 80|B22| 55 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App3|30| I03 | GE 0/0/1.1 | 90 | Best | 0| 58| 20|B03| 90 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App3|30| I31 |# GW1-System IP| 80 | Good | 0| 65| 30|B31| 78 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
|App3|30| I32 |# GW2-System IP| 75 | Acct | 2|130| 90|B32| 72 |
+----+--+-----+---------------+-----+------+---+---+---+---+-----+
L: Loss D: Delay
J: Jitter B: Bandwidth
Acct: Acceptable O_QoS: Original QoS
F_QoS: Final QoS
Figure 2: CPE1's SaaS Path Perfermance Metrics Table
Upon receiving the QoS score from the GW router, CPE1 will calculates
the Final QoS score based on the SD-WAN tunnel status and and the
received QoS score. When a user of CPE1 accesses a SaaS
applications, CPE1 determines the best performing path toward the
SaaS application based on the Final QoS score (F_QoS).
For example If App1 is the target SaaS Application, select the SaaS
path that passes through GW2 with the Path Index I16 because it has
the highest score: 88. If App2 is the target SaaS Application,
select the SaaS path that passes through GW1 with the Path Index I21
because it has the highest score: 75. If App3 is the target SaaS
application, select the local SaaS path with the Path Index I03
because it has the highest score: 90.
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4. The SaaS Path Performance Route
The BGP SD-WAN NLRI as defined in [I-D.ietf-idr-sdwan-edge-discovery]
is shown below:
+-----------------------------------+
| Route Type (2 octets) |
+-----------------------------------+
| Length (2 octets) |
+-----------------------------------+
~ ~
| Type Specific Value (variable) |
~ ~
+-----------------------------------+
Figure 3: BGP SD-WAN NLRI
Where:
* Route (NLRI) Type: 2 octet value to define the encoding of the
rest of the SD-WAN NLRI.
* Length: 2 octets of length expressed in bits as defined in
[RFC4760].
This document defines an additional route type to be used for the
advertisement of the SaaS Path Performance Metrics between different
enterprise sites:
* NLRI Route Type: 2
* Name: SaaS Path Performance Route
4.1. The SaaS Path Performance Route Encoding
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+--------------------+
| Route Type = 2 | 2 octets
+--------------------+
| Length | 2 octets
+--------------------+
| Site ID | 4 octets
+--------------------+
| APP ID | 4 octets
+--------------------+
| APP Req | 1 octet
+--------------------+
| Path Index Type | 1 octet
+--------------------+
| Path Index Value | 3 or 4 or 16 octets
+--------------------+
| SD-WAN-Node-ID | 4 or 16 octets
+--------------------+
Figure 4: SaaS Path Performance Route
Where:
* Route Type: 2, SaaS Path Performance Route
* Length: 2 octets of length expressed in bits as defined in
[RFC4760].
* Site ID: 4 octets, A site ID is a unique identifier of an
enterprise site in the SD-WAN network.
* APP ID: 4 octets, SaaS Application ID, a unique Application ID to
identify different applications. Application may be deployed
using different IP address in different area. Thus an ID is
needed to identify the application.
* APP Req: 1 octet, Application requirement to indicate the
application requirement of the path quality. For example, an real
time video conferencing application requires higher quality than a
background file backup application. The value includes:
- Type = 1: default;
- Type = 2: Medium;
- Type = 3: High;
* Path Index Type: Indicates the type of the path index.
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* Path Index Value: a Path Index Type specific Value:
- Type 1, the Path Index Value is a 4-byte local index value,
which is used to identify an outbound interface for accessing
SaaS applications.
- Type 2, the Path Index Value is a 3-byte MPLS label, which is
used to identify an outbound interface for accessing the SaaS
application.
- Type 3, The Path Index Value is a 16-byte SRv6 SID, which is
used to identify an outbound interface for accessing a SaaS
application, and its Endpoint Behavior is End.DT2SaaSPath:
Decapsulate SRv6 packet, then send the packet to the target
SaaS application from the outbound interface indicated by the
SRv6 SID.
* SD-WAN Node ID: The node's IPv4 or IPv6 address.
4.2. The SaaS Path Performance Metrics Encoding
The Metadata Path Attribute has been as defined in [I-D.ietf-idr-5g-
edge-service-metadata]. This document introduces some additional
Sub-TLVs to encode the SaaS Path Performance Metrics and SaaS
Application Information.
Another option is to use the above Sub-TLVs in the Tunnel
Encapsulation Attribute [RFC9012]. In this option, the tunnel type
"SaaS Application Path Performance" is added.
4.2.1. The SaaS Path Delay Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Delay Sub-Type = TBD1 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Delay |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: SaaS Path Delay Sub-TLV
Where:
* Delay Sub-Type: TBD by IANA.
* Length: 2 octets, the total number of octets of the value field.
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* Delay: 2 octets, this field indicates the packet transmission
delay, in milliseconds.
4.2.2. The SaaS Path Loss Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Loss Sub-Type = TBD2 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Loss |
+-+-+-+-+-+-+-+-+
Figure 6: SaaS Path Loss Sub-TLV
Where:
* Loss Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Loss: 1 octet, this field indicates the packet loss rate (%).
4.2.3. The SaaS Path Jitter Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Jitter Sub-Type = TBD3 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Jitter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: SaaS Path Jitter Sub-TLV
Where:
* Jitter Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Jitter: 2 octets, this field indicates the jitter on the SaaS
Path. Range: 1 through 1000 milliseconds
4.2.4. The SaaS Path Bandwidth Sub-TLV format
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth Sub-Type = TBD4 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Bandwidth |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: SaaS Path Bandwidth Sub-TLV
Where:
* Bandwidth Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Bandwidth: 4 octets, this field indicates the bandwidth of the
SaaS Path.
4.2.5. The SaaS Path Status Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Status Sub-Type = TBD5 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Status |
+-+-+-+-+-+-+-+-+
Figure 9: SaaS Path Status Sub-TLV
Where:
* Status Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Status: 1 octet, Network assessment, there are 6 levels as
follows:
- 100: Best
- 80: Good, Meets recommendations
- 60: Acceptable
- 40: Users may experience issues
- 20: Users may complain
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- 0: Network problems
4.2.6. The SaaS Path QoS Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| QoS Sub-Type = TBD6 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| QoS |
+-+-+-+-+-+-+-+-+
Figure 10: SaaS Path QoS Sub-TLV
Where:
* QoS Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* QoS: 1 octet, Quality of Service, 1-100, with 1 being the worst,
and 100 being the best. The QoS value is calculated based on the
values of Loss, Jitter, Delay, and Status.
4.2.7. The SaaS Application Name Sub-TLV format
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SaaS AppName Sub-Type = TBD7 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
| Application Name (1-n Octets) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: Saas Application Name Sub-TLV
Where:
* SaaS AppName Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Application Name: The name of the application represented as a
string, such as Salesforce, Dropbox, Office 365, and so on.
4.2.8. The SaaS Application Domain Name Sub-TLV format
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0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AppDomainName Sub-Type = TBD8 | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ ~
| Application Domain Name (Variable) |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 12: SaaS Application Domain Name Sub-TLV
Where:
* AppDomainName Sub-Type: TBD by IANA
* Length: 2 octets, the total number of octets of the value field.
* Application Domain Name: The domain name of the application
represented as a string, such as www.salesforce.com,
www.baidu.com, www.iana.org, www.dropbox.com, www.microsoft.com,
and so on.
5. Security Considerations
TBD.
6. IANA Considerations
TBD.
7. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/rfc/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
Appendix A. Contributors
Shunwan Zhuang Huawei Email: zhuangshunwan@huawei.com
Penghe Tang Huawei Technologies Email:
tangpenghe@huawei.com@huawei.com
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Authors' Addresses
Cheng Sheng
Huawei
Beiqing Road
Beijing
China
Email: shengcheng@huawei.com
Hang Shi (editor)
Huawei
Beiqing Road
Beijing
China
Email: shihang9@huawei.com
Linda Dunbar
Futurewei
United States
Email: linda.dunbar@futurewei.com
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