Internet DRAFT - draft-saldana-tsvwg-simplemux
draft-saldana-tsvwg-simplemux
TSVWG J. Saldana
Internet-Draft CIRCE Technology Center
Intended status: Standards Track 28 December 2023
Expires: 30 June 2024
Simplemux. A generic multiplexing protocol
draft-saldana-tsvwg-simplemux-12
Abstract
The high amount of small packets present in nowaday's networks
results in a low efficiency, as the size of both the headers and the
payload in these packets can be comparably large, often falling
within the same order of magnitude. In some situations, multiplexing
(i.e. aggregating) a number of small packets into a bigger one is
desirable to improve the efficiency. For example, a number of small
packets can be sent together between a pair of machines if they share
a common network path. This may happen between machines in different
locations or even inside a datacenter with a number of servers
hosting virtual machines. The traffic profile can be shifted from
small to larger packets, thus reducing the network overhead and the
number of packets per second to be managed by intermediate devices.
This document describes Simplemux, a protocol able to encapsulate a
number of packets belonging to different protocols into a single
packet. Small headers (separators) are added at the beginning of
each multiplexed packet, including some flags, the packet length and
a "Protocol" field. The presence of this "Protocol" field allows it
to aggregate packets belonging to any protocol (the "multiplexed
packets"), in a single packet belonging to other (or the same)
protocol (the "tunneling protocol").
To reduce the overhead, the size of the multiplexing headers is kept
very low (it may be a single byte when multiplexing packets of small
size).
About This Document
This note is to be removed before publishing as an RFC.
Status information for this document may be found at
https://datatracker.ietf.org/doc/draft-saldana-tsvwg-simplemux/.
Discussion of this document takes place on the Transport Area Working
Group (tsvwg) Working Group mailing list (mailto:tsvwg@ietf.org),
which is archived at https://mailarchive.ietf.org/arch/browse/tsvwg/.
Subscribe at https://www.ietf.org/mailman/listinfo/tsvwg/.
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Status of This Memo
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This Internet-Draft will expire on 30 June 2024.
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Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Benefits of multiplexing . . . . . . . . . . . . . . . . . . 5
4. Existing multiplexing protocols . . . . . . . . . . . . . . . 6
4.1. Tmux . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2. PPPmux . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.3. Advantages of Simplemux . . . . . . . . . . . . . . . . . 7
5. Scenarios of interest . . . . . . . . . . . . . . . . . . . . 7
6. Protocol description . . . . . . . . . . . . . . . . . . . . 7
6.1. Fast flavor . . . . . . . . . . . . . . . . . . . . . . . 8
6.2. Compressed flavor . . . . . . . . . . . . . . . . . . . . 8
6.2.1. First Simplemux header . . . . . . . . . . . . . . . 8
6.2.2. Non-first Simplemux header . . . . . . . . . . . . . 11
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
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9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
9.1. Normative References . . . . . . . . . . . . . . . . . . 16
9.2. Informative References . . . . . . . . . . . . . . . . . 17
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
The high amount of small packets present in nowaday's networks
results in a low efficiency, when the size of the headers and the
payload fall within the same order of magnitude. In some situations,
multiplexing (i.e. aggregating) a number of small packets into a
bigger one is desirable to improve the efficiency. In these cases, a
number of small packets can be sent together between a pair of
machines if they share a common network path. This may happen
between machines in different locations or even inside a datacenter
with a number of servers hosting virtual machines. The traffic
profile can be shifted from small to larger packets, thus reducing
the overhead and the number of packets per second to be managed by
intermediate devices.
This document describes Simplemux, a protocol able to encapsulate a
number of packets belonging to different protocols into a single
packet.
Simplemux generic: it includes a "Protocol" field, so it can be used
to aggregate a number of packets belonging to any protocol, in a
single packet belonging to other (or the same) protocol.
In this document we will talk about the "multiplexed" protocol, and
the "tunneling" protocol, being Simplemux the "multiplexing"
protocol. The "external header" will be the one of the "tunneling"
protocol. In this document, we will also refer to the Simplemux
header with the terms "separator," "Simplemux separator" or "mux
separator". In the figures we will also use the abbreviation "Smux".
These elements are presented in Figure 1.
+--------------------------------+
| Multiplexed Packet | Multiplexed protocol
+--------------------------------+
| Simplemux header/separator | Multiplexing protocol
+--------------------------------+
| Tunneling header | Tunneling protocol
+--------------------------------+
Figure 1
A Simplemux packet will have the structure shown in Figure 2.
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+-------------++-------------+------++-------------+------+
|tunneling hdr||Simplemux hdr|packet||Simplemux hdr|packet| ...
+-------------++-------------+------++-------------+------+
Figure 2
As an example, if a number of small IPv6 packets have to traverse an
IPv4 network, they can be multiplexed together into a single IPv4
packet. In this case, IPv4 will be the "tunneling" protocol and IPv6
will be the "multiplexed" protocol. The IPv4 header is called in
this case the "tunneling" or the "external" header. The scheme of
this packet will be(the "Protocol" field inside the Simplemux header
will be 41 (IPv6), according to IANA Assigned Internet Protocol
Numbers):
+------++-------------+-----------++-------------+-----------+
| IPv4 ||Simplemux hdr|IPv6 packet||Simplemux hdr|IPv6 packet|...
+------++-------------+-----------++-------------+-----------+
Figure 3
Another example is the tunneling of Ethernet frames between different
networks using UDP. In this case, IPv4/UDP will be the "tunneling"
protocol and Ethernet will be the "multiplexed" protocol. The IPv4/
UDP header is called in this case the "tunneling" or the "external"
header. The scheme of this packet will be (the "Protocol" field
inside the Simplemux header will be 143 (Ethernet), according to IANA
Assigned Internet Protocol Numbers):
+------+---++-------------+---------++-------------+---------+
| IPv4 |UDP||Simplemux hdr|Eth frame||Simplemux hdr|Eth frame|...
+------+---++-------------+---------++-------------+---------+
Figure 4
Simplemux has two flavors:
* Fast: all the separators are 3-byte long, and all have the same
structure, so it sacrifices some compression on behalf of speed.
* Compressed: it tries to compress the separators as much as
possible. For that aim, some single-bit fields are used.
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2. Conventions
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. Benefits of multiplexing
The benefits of multiplexing are:
- Tunneling a number of packets together. If a number of packets
have to be tunneled through a network segment, they can be
multiplexed and then sent together using a single external header.
This will avoid the need for adding a tunneling header to each of the
packets, thus reducing the overhead.
- Reduction of the amount of packets per second in the network.
Network equipment has a limitation in terms of the number of packets
per second it can manage, i.e. many devices are not able to send
small packets back to back due to processing delay.
- Bandwidth reduction. The presence of high rates of tiny packets
translates into an inefficient usage of network resources, so the
overhead introduced by low-efficiency flows can be reduced. When
combined with header compression, as done in TCRTP [RFC4170]
multiplexing may produce significant bandwidth savings, which are
interesting for network operators, since they may alleviate the
traffic load in their networks.
- Energy savings: a lower amount of packets per second will reduce
energy consumption in network equipment since, according to [Bolla],
internal packet processing engines and switching fabric require 60%
and 18% of the power consumption of high-end routers respectively.
Thus, reducing the number of packets to be managed and switched will
reduce the overall energy consumption. The measurements deployed in
[chab] on commercial routers corroborate this: tests showed that
energy consumption gets reduced, since a non-negligible amount of
energy is associated to header processing tasks, and not only to the
sending of the packet itself.
Some tests measuring the benefits of Simplemux were published in
[Saldana].
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4. Existing multiplexing protocols
Different multiplexing protocols have been approved by the IETF in
the past:
4.1. Tmux
TMux [RFC1692] is able to combine multiple short transport segments,
independent of application type, and send them between a server and
host pair. As stated in the reference, "The TMux protocol is
intended to optimize the transmission of large numbers of small data
packets. In particular, communication load is not measured only in
bits per seconds but also in packets per seconds, and in many
situation the latter is the true performance limit, not the former.
The proposed multiplexing is aimed at alleviating this situation."
A TMux message appears as:
+------++--------+-----------------++--------+-----------------+
|IP hdr||TMux hdr|Transport segment||TMux hdr|Transport segment|...
+------++--------+-----------------++--------+-----------------+
Figure 5
Therefore, the Transport Segment is not an entire IP packet, since it
does not include the IP header.
TMux works "between a server and host pair," so it multiplexes a
number of segments between the same pair of machines. However, there
are scenarios where a number of low-efficiency flows share a common
path, but they do not travel between the same pair of end machines.
4.2. PPPmux
PPPMux [RFC3153] "sends multiple PPP encapsulated packets in a single
PPP frame. As a result, the PPP overhead per packet is reduced."
Thus, it is able to multiplex complete IP packets, using separators.
However, the use of PPPMux requires the use of PPP and L2TP to
multiplex a number of packets together, as done in TCRTP [RFC4170].
Thus, it introduces more overhead and complexity.
Using PPPMux, an IP packet including a number of packets appears as:
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+------++-------+-------++----------+------++----------+------+
|IP hdr|L2TP hdr|PPP hdr||PPPMux hdr|packet||PPPMux hdr|packet| ...
+------++-------+-------++----------+------++----------+------+
Figure 6
The scheme proposed by PPPMux is similar to the Compound-Frames of
PPP LCP Extensions [RFC1570]. The key differences are that PPPMux is
more efficient and that it allows concatenation of variable sized
frames.
4.3. Advantages of Simplemux
The definition of a protocol able to multiplex complete packets,
avoiding the need of using other protocols as e.g. PPP is seen as
convenient. The multiplexed packets MAY belong to any protocol,
since a "Protocol" field is added to each of them. Note that
Ethernet frames can also be aggregated together.
5. Scenarios of interest
Simplemux works between a pair of machines. It creates a tunnel
between an "ingress" and an "egress". They MAY be the endpoints of
the communication, but they MAY also be middleboxes able to multiplex
packets belonging to different flows. Different mechanisms MAY be
used in order to classify flows according to some criteria (sharing a
common path, kind of service, etc.) and to select the flows to be
multiplexed and sent to the egress (see Figure 7).
+-------+
| | +---------+ +---------+
| | ---> |Simplemux| _ _ |Simplemux| -->
|classif| ---> | ingress | ===> ( ` )_ ===> | egress | -->
| | +---------+ ( Network `) +---------+
| | (_ (_ . _) _)
+-------+
<--------Simplemux-------->
Figure 7
6. Protocol description
Simplemux has two flavors:
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* Fast: all the separators are 3-byte long, and all have the same
structure, so it sacrifices some compression on behalf of speed.
* Compressed: it tries to compress the separators as much as
possible. For that aim, some single-bit fields are used.
6.1. Fast flavor
In Fast flavor, all the Simplemux headers have the same format, with
two fields:
- Length (LEN, 16 bits) of the multiplexed packet (in bytes).
- Protocol (8 bits) of the multiplexed packet, according to IANA
"Assigned Internet Protocol Numbers".
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | |
| Length | Protocol |
| (16 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8
6.2. Compressed flavor
In Compressed flavor, the Simplemux header has two different forms:
one for the "First Simplemux header," and another one for the rest of
the Simplemux headers (called "Non-first Simplemux headers"):
6.2.1. First Simplemux header
In is placed after the tunneling header, and before the first
multiplexed packet.
In order to allow the multiplexing of packets of any length, the
number of bytes expressing the length is variable, and a field called
"Length Extension" (LXT, one bit) is used to flag if the current byte
is the last one including length information. This is the structure
of a First Simplemux header:
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- Single Protocol Bit (SPB, one bit) only appears in the first
Simplemux header. It is set to 1 if all the multiplexed packets
belong to the same protocol (in this case, the "Protocol" field will
only appear in the first Simplemux header). It is 0 when each packet
MAY belong to a different protocol.
- Length Extension (LXT, one bit) is 0 if the current byte is the
last byte where the length of the first packet is included, and 1 in
other case.
- Length (LEN, 6, 13, 20, etc. bits): This is the length of the
multiplexed packet (in bytes). If the length of the multiplexed
packet is less than 64 bytes (less than or equal to 63 bytes), the
first LXT is 0 and the 6 bits of the length field are the length of
the multiplexed packet. If the length of the multiplexed packet is
equal or greater than 64 bytes, additional bytes are added. The
first bit of each of the added bytes is the LXT. If LXT is set to 1,
it means that there is an additional byte for expressing the length.
This allows to multiplex packets of any length (see the next
figures).
- Protocol (8 bits) of the multiplexed packet, according to IANA
"Assigned Internet Protocol Numbers."
A First Simplemux header before a packet smaller than 64 (2^6) bytes
will be 2 bytes long:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|L| | |
|P|X| Length | Protocol |
|B|T| (6 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^
|
0
Figure 9
A First Simplemux header before a packet with a length greater or
equal to 64 bytes, and smaller than 8192 bytes (2^13) will be 3 bytes
long:
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0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|L| |L| | |
|P|X| Length 1 |X| Length 2 | Protocol |
|B|T| (6 bits) |T| (7 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^
| |
1 0
Figure 10
In this case, the length of the packet will be the number expressed
by the concatenation of the bits of Length 1 and Length 2 (total 13
bits). Length 1 includes the 6 most significant bits and Length 2
the 7 less significant bits.
A First Simplemux header before a packet with a length greater of
equal to 8192 bytes, and smaller than 1048576 bytes (2^20), will be 4
bytes long:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|S|L| |L| |L| | |
|P|X| Length 1 |X| Length 2 |X| Length 3 | Protocol |
|B|T| (6 bits) |T| (7 bits) |T| (7 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^ ^
| | |
1 1 0
Figure 11
In this case, the length of the packet will be the number expressed
by the concatenation of the bits of Length 1 , Length 2 and Length 3
(total 20 bits). Length 1 includes the 6 most significant bits and
Length 3 the less 7 significant bits.
More bytes can be added to the length if required, using the same
scheme: 1 LXT byte plus 7 bits for expressing the length.
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6.2.2. Non-first Simplemux header
The Non-first Simplemux headers also employ a format allowing the
multiplexing of packets of any length, so the number of bytes
expressing the length is variable, and the field Length Extension
(LXT, one bit) is used to flag if the current byte is the last one
including length information. This is the structure of a Non-first
Simplemux header:
- Length Extension (LXT, one bit) is 0 if the current byte is the
last byte where the length of the packet is included, and 1 in other
case.
- Length (LEN, 7, 14, 21, etc. bits): This is the length of the
multiplexed packet (in bytes), not including the length field. If
the length of the multiplexed packet is less than 128 bytes (less
than or equal to 127 bytes), LXT is 0 and the 7 bits of the length
field represent the length of the multiplexed packet. If the length
of the multiplexed packet is greater than 127 bytes, additional bytes
are added. The first bit of each of the added bytes is the LXT. If
LXT is set to 1, it means that there is an additional byte for
expressing the length. This allows to multiplex packets of any
length (see the next figures).
- Protocol (8 bits) field of the multiplexed packet, according to
IANA "Assigned Internet Protocol Numbers". It only appears in Non-
first headers if the Single Protocol Bit (SPB) of the First Simplemux
header is set to 1.
As an example, a Non-first Simplemux header before a packet smaller
than 128 bytes, when the protocol bit has been set to 0 in the First
header, will be 1 byte long:
0
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|L| |
|X| Length |
|T| (7 bits) |
+-+-+-+-+-+-+-+-+
^
|
0
SPB = 1 in the first header
Figure 12
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A Non-first Simplemux header before a packet witha a length greater
or equal to 128 bytes, and smaller than 16384 (2^14), when the
protocol bit has been set to 0 in the First header, will be 2 bytes
long:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| |L| |
|X| Length 1 |X| Length 2 |
|T| (7 bits) |T| (7 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^
| |
1 0
SPB = 1 in the first header
Figure 13
A Non-first Simplemux header before a packet with a length greater or
equal to 16384 bytes, and smaller than 2097152 bytes (2^21), when the
protocol bit has been set to 0 in the First header, will be 3 bytes
long:
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| |L| |L| |
|X| Length 1 |X| Length 2 |X| Length 3 |
|T| (7 bits) |T| (7 bits) |T| (7 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^ ^
| | |
1 1 0
SPB = 1 in the first header
Figure 14
In this case, the length of the packet will be the number expressed
by the concatenation of the bits of Length 1, Length 2 and Length 3
(total 21 bits). Length 1 includes the 7 most significant bits and
Length 3 the 7 less significant bits.
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More bytes can be added to the length if required, using the same
scheme: 1 LXT byte plus 7 bits for expressing the length.
A Non-first Simplemux header before a packet smaller than 128 bytes,
when the protocol bit has been set to 1 in the First header, will be
2 bytes long:
0 1
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| | |
|X| Length | Protocol |
|T| (7 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^
|
0
SPB = 0 in the first header
Figure 15
A Non-first Simplemux header before a packet with a length greater or
equal to 128 bytes, and smaller than 16384 (2^14), when the protocol
bit has been set to 1 in the First header, will be 3 bytes long:
0 1 2
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| |L| | |
|X| Length 1 |X| Length 2 | Protocol |
|T| (7 bits) |T| (7 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^
| |
1 0
SPB = 0 in the first header
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Figure 16
A Non-first Simplemux header before a packet with a length greater of
equal to 16384 bytes, and smaller than 2097152 bytes (2^21), when the
protocol bit has been set to 1 in the first header, will be 4 bytes
long:
0 1 2 3
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|L| |L| |L| | |
|X| Length 1 |X| Length 2 |X| Length 3 | Protocol |
|T| (7 bits) |T| (7 bits) |T| (7 bits) | (8 bits) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
^ ^ ^
| | |
1 1 0
SPB = 0 in the first header
Figure 17
In this case, the length of the packet will be the number expressed
by the concatenation of the bits of Length 1, Length 2 and Length 3
(total 21 bits). Length 1 includes the 7 most significant bits and
Length 3 the 7 less significant bits.
More bytes can be added to the length if required, using the same
scheme: 1 LXT byte plus 7 bits for expressing the length.
Next, some examples of the whole bundles are presented
Case 1: All the packets belong to the same protocol: The first
Simplemux header will be 2 or 3 bytes (for usual packet sizes), and
the other Simplemux headers will be 1 or 2 bytes. For small packets
(length < 128 bytes), the Simplemux header will only require one
byte.
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LXT LXT LXT LXT
| | | |
V V V V
+---++-+-+---+--------+---++-+---+---++-+---+-+---+---++
|tun||1|0|len|Protocol|pkt||0|len|pkt||1|len|0|len|pkt||...
+---++-+-+---+--------+---++-+---+---++-+---+-+---+---++
^ ^ ^ ^ ^
| | | | |
SPB (6 bits) (7 bits) (14 bits)
LXT LXT LXT LXT LXT
| | | | |
V V V V V
+---++-+-+---+-+---+--------+---++-+---+---++-+---+-+---+---++
|tun||1|1|len|0|len|Protocol|pkt||0|len|pkt||1|len|0|len|pkt||..
+---++-+-+---+-+---+--------+---++-+---+---++-+---+-+---+---++
^ ^ ^ ^ ^ ^
| | | | | |
SPB (13 bits) (7 bits) (14 bits)
Figure 18
Case 2: Each packet MAY belong to a different protocol: All the
Simplemux headers will be 2 or 3 bytes (for usual packet sizes).
LXT LXT LXT LXT
| | | |
V V V V
+---++-+-+---+----+---++-+---+----+---++-+---+-+---+----+---++
|tun||0|0|len|Prot|pkt||0|len|Prot|pkt||1|len|0|len|Prot|pkt||..
+---++-+-+---+----+---++-+---+----+---++-+---+-+---+----+---++
^ ^ ^ ^ ^
| | | | |
SPB (6 bits) (7 bits) (14 bits)
LXT LXT LXT LXT LXT
| | | | |
V V V V V
+---++-+-+---+-+---+----+---++-+---+----+---++-+---+-+---+----+---++
|tun||0|1|len|0|len|Prot|pkt||0|len|Prot|pkt||1|len|0|len|Prot|pkt||.
+---++-+-+---+-+---+----+---++-+---+----+---++-+---+-+---+----+---++
^ ^ ^ ^ ^ ^
| | | | | |
SPB (13 bits) (7 bits) (14 bits)
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Figure 19
7. IANA Considerations
A protocol number for Simplemux should be requested to IANA.
As a provisional solution for IP networks, the ingress and the egress
optimizers may agree on a UDP port, and use IP/UDP as the
multiplexing protocol.
8. Security Considerations
Simplemux protocol has been developed in such a way that packet
aggregation and security can be simultaneously applied to the same
traffic flows, i.e. a single security header could protect a number
of packets belonging to different flows.
As a consequence, the overall efficiency could be improved, as the
number of security headers could be reduced from N to 1 (being N the
number of multiplexed packets).
9. References
9.1. 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/info/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/info/rfc8174>.
[RFC1570] Simpson, W., Ed., "PPP LCP Extensions", RFC 1570,
DOI 10.17487/RFC1570, January 1994,
<https://www.rfc-editor.org/info/rfc1570>.
[RFC3153] Pazhyannur, R., Ali, I., and C. Fox, "PPP Multiplexing",
RFC 3153, DOI 10.17487/RFC3153, August 2001,
<https://www.rfc-editor.org/info/rfc3153>.
[RFC4170] Thompson, B., Koren, T., and D. Wing, "Tunneling
Multiplexed Compressed RTP (TCRTP)", BCP 110, RFC 4170,
DOI 10.17487/RFC4170, November 2005,
<https://www.rfc-editor.org/info/rfc4170>.
Saldana Expires 30 June 2024 [Page 16]
Internet-Draft Simplemux December 2023
9.2. Informative References
[RFC1692] Cameron, P., Crocker, D., Cohen, D., and J. Postel,
"Transport Multiplexing Protocol (TMux)", RFC 1692,
DOI 10.17487/RFC1692, August 1994,
<https://www.rfc-editor.org/info/rfc1692>.
[Bolla] Bolla, R., Bruschi, R., Davoli, F., and F. Cucchietti,
"Energy Efficiency in the Future Internet: A Survey of
Existing Approaches and Trends in Energy-Aware Fixed
Network Infrastructures", IEEE Communications Surveys and
Tutorials vol.13, no.2, pp.223,244, 2011.
[chab] Chabarek, J., Sommers, J., Barford, P., Estan, C., Tsiang,
D., and S. Wright, "Power Awareness in Network Design and
Routing", INFOCOM 2008. The 27th Conference on Computer
Communications. IEEE pp.457,465, 2008.
[Saldana] Saldana, J., Forcen, I., Fernandez-Navajas, J., and J.
Ruiz-Mas, "Improving Network Efficiency with Simplemux",
IEEE CIT 2015, International Conference on Computer and
Information Technology pp. 446-453, 26-28 October 2015,
Liverpool, UK., 2015.
Author's Address
Jose Saldana
CIRCE Technology Center
Email: jmsaldana@fcirce.es
Saldana Expires 30 June 2024 [Page 17]
