Internet Area WG L. Muscariello
Internet-Draft G. Carofiglio
Intended status: Informational J. Auge
Expires: May 2, 2020 M. Papalini
Cisco Systems Inc.
October 30, 2019
Hybrid Information-Centric Networking
draft-muscariello-intarea-hicn-03
Abstract
This document describes the hybrid information-centric networking
(hICN) architecture for IPv6. The specifications describe a way to
implement information-networking functionalities into IPv6. The
objective is to use IPv6 without creating overlays with a new packet
format as an additional encapsulation. The intent of the present
design is to introduce some IPv6 routers in the network with
additional packet processing operations to implement ICN functions.
Moreover, the current design is tightly integrated into IPv6 to allow
easy interconnection to IPv6 networks with the additional design
objective to exploit existing IPv6 protocols as much as possible as
they are, or extend them where needed.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on May 2, 2020.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
2. Architecture . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. End-points . . . . . . . . . . . . . . . . . . . . . . . 6
2.2. Naming . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2.1. Name prefix . . . . . . . . . . . . . . . . . . . . . 7
2.2.2. Name Suffix . . . . . . . . . . . . . . . . . . . . . 8
2.3. Packet Format . . . . . . . . . . . . . . . . . . . . . . 8
2.3.1. Interest Packet . . . . . . . . . . . . . . . . . . . 8
2.3.2. Data Packet . . . . . . . . . . . . . . . . . . . . . 9
2.4. Packet cache . . . . . . . . . . . . . . . . . . . . . . 12
2.5. Forwarding . . . . . . . . . . . . . . . . . . . . . . . 12
2.5.1. Interest Path . . . . . . . . . . . . . . . . . . . . 13
2.5.2. Data Path . . . . . . . . . . . . . . . . . . . . . . 15
3. Security . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4. The End-host model and End-to-End considerations . . . . . . 19
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20
6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 20
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.1. Normative References . . . . . . . . . . . . . . . . . . 20
7.2. Informative References . . . . . . . . . . . . . . . . . 21
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
1. Introduction
The objective of this document is to describe hybrid ICN, a network
protocol that integrates ICN in IPv6, at a minimum cost in terms of
required modifications in end-points and routers and in a way to
guarantee transparent interconnection with IP without using overlays.
The ICN reference design used in this document is CCNx as described
in [RFC8569] and [RFC8609]. IPv6 is used as described in [RFC8200].
There are some basic design principles behind the hICN architecture
that are implemented by the design reported below that can be
summarized as follows:
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o (i) the network can transport many different kinds of applications
as IPv6, i.e. hICN can serve content-distribution or real-time
applications, to cite examples with very different requirements.
hICN is not a content-distribution network;
o (ii) it provides connection-less and location independent
communications by identifying data with unique global names,
instead of naming network interfaces (locator) or end-hosts (end-
host identifiers) as in LISP [RFC6830].
o (iii) data is retrieved by an end-point by issuing requests and a
node accepts a data packet from an ingress interface if and only
if at least one matching request packet is stored in the local
cache of the node, otherwise the data packet is dropped;
o (iv) basic security services are provided by the architecture:
authenticity of the data producer and data integrity. A
cryptographic signature over a security envelop is computed by the
producer (using its own private key) and must be verified by the
consumer (using the producer's public key). The security envelop
can be as small as a single data packet or cover groups of packets
using the technique of the transport manifest [MAN].
1.1. Notational Conventions
The words "MUST", "MUST NOT", "SHOULD", and "MAY" are used in this
document. It's not shouting; when these words are capitalized, they
have a special meaning as defined in [RFC2119].
2. Architecture
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+---------------------+
| | Data packets
| End-host | +-----------+ +-----------+
| +-------> | | | |
| +------------+ | | IPv6 | | hICN |
| | Producer | +-----------+ router +----------+ router |
| | end-point | | | | | |
| +------------+ | <------+ +----+------+ +------+----+
| | | |
+---------------------+ Interest | |
packets | |
| |
| |
| |
+----+------+ +----+------+
| | | |
| hICN | | IPv6 |
+----------------+ router +------------+ network |
+ ^ | | | | |
| | | +-----------+ +--------+--+
| | | |
v | | |
| | |
+---------------------+ Interest packets |
| +------------+ | +--------> +-----------+ |
| | Consumer | | | | |
| | end-point | +-----------------------+ hICN +-----+
| +------------+ | | router |
| | <-------+ | |
| End-host | +-----------+
| | Data packets
+---------------------+
Figure 1: General overview of an hICN end-to-end communication.
The communication model described in this document covers the
transport and the network layer.
The network layer includes the forwarding plane only and does not
consider the routing plane. hICN network layer is about using the
IPv6 FIB to determine a next hop router to forward requests or using
a local packet cache to determine if an incoming request can be
satisfied locally. The hICN forwarding plane takes care of
forwarding replies by using information stored in cached requests.
The packet pipeline of an hICN node always includes a lookup in a
packet cache for both requests and replies. The packet cache is a
mandatory component that is added to the usual IPv6 packet processing
pipeline. Requests and replies carry an immutable data name end-to-
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end, in packet header fields as described in the following sections.
Moreover, requests and replies carry locators as mutable packet
header fields. A locator, i.e. an interface identifier, is changed
every time a packet is sent to another hICN node. A detailed
description of how locators are modified along the path between end-
points is reported in the following sections.
It is assumed that existing routing protocols, working for IPv6,
should be reused as much as possible as they are. Improvements to
existing routing protocols are out of scope and might be developed in
other documents to better exploit features made available by the hICN
forwarding plane. For instance, hICN forwarding plane can take
advantage of the ability of a routing protocol to provide multiple
routes for a given destination or more generally compute routes for
destinations that are multi-instantiated [MIR]. This topic is
important but out of scope for this document.
The hICN network architecture can run on top of any link-layer that
supports IPv6. hICN data names are globally routable names which are
visible to the transport layer end-points. Conversely, the transport
layer has no visibility of addresses of network interfaces. The
network layer forwards two kinds of protocol data units: the request
and the reply, called interest and data packets.
The hICN network layer offers a communication service to the
transport layer in the end-points by means of a local unidirectional
channel that we call local or application face. This channel is used
by the transport layer to send requests and receive replies or to
send replies upon receptions of requests.
A transport end-point is always bound to a unidirectional channel
that is used to either send data or receive data. The former end-
point is called data producer while the latter data consumer. The
producer end-point produces data under a location independent name,
which is an IPv6 prefix. A consumer end-point fetches data by using
the non ambiguous name as provided by the producer. The producer
end-point is responsible for managing the usage of the prefix in
terms of provisioning, association to applications and its
revocation.
The transport end-point offers two kinds of services to applications:
a producer and a consumer service. The service is instantiated in
the application by opening communication sockets with an API to
perform basic transport service operations: allocation,
initialization, configuration, data transmission and reception.
The producer and consumer sockets can implement different types of
services such as stream or datagram, reliable or unreliable. In all
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cases all transport services are connection-less, meaning that a
producer transport service produces named data in a socket memory
that is accessible by any valid request coming from one or multiple
consumers. The consumer, on the other hand, retrieve named data
using location independent names which are not tied to any interface
identifier (also called locator). This transport model allows to
implement reliable consumer mobility without any special mobility
management protocol. hICN supports communication of multi-homed end-
hosts without any special treatment in the transport layer. The hICN
network layer can also implement robust usage of multi-path
forwarding in IPv6 networks as balanced request/reply flows self-
stabilize network congestion see [CCN],[NDN], [RAQ] .
A data packet is an IPv6 packet with a transport layer header
carrying data from an application that produces data. An interest
packet is an IPv6 packet with a transport layer header and is used to
unambiguously fetch a data packet from a producer end point.
2.1. End-points
In hICN we introduce two new kinds of endpoints: the producer and the
consumer. We identify two kind of communication sockets each with a
specific API: the producer and consumer sockets. These socket types
are designed to exchange data in a multi-point to multi-point manner.
In (h)ICN we have the same concept that is applied to a network where
memories are distributed across the communication path. The first
memory in the path is the production buffer of the producer end-point
that forges Data Packets and copies them into a shared memory
isolated into a namespace. Consumer sockets can retrieve data from
such memory by using the (h)ICN network layer. The model just
described is an inter-process communication example (IPC) that
requires data to cross a communication network by using a transport
protocol.
The way consumers and producers synchronize depends on application
requirements and the transport layer exposes a variety of services:
stream/datagram, reliable/unreliable, with or without latency budgets
etc. Independently of the specific requirements of the applications,
producer sockets always perform data segmentation from the upper
layer into Data Packets, as well as compute digital signatures on the
packet security envelop. This envelop can also be computed across a
group of packets, by including a cryptographic hash of each packet
into the transport manifest, and eventually signing only such
manifest.
The consumer socket, on the other end, always performs reassembly of
Data Packets, hash integrity verification and signature verification.
This is common to all architectures in (h)ICN. The usual assumption
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is that the producer socket uses an authentic-able identity while
using namespaces that it has been assigned. The end-point must be
able to manage the mapping of her identity and the allocated
namespace by issuing digital certificates about the mapping. The
consumer end-point must retrieve the associated certificate to
perform the basic operations. It is out of scope for this document
how to design and implement a scalable system to perform such
certificate operations.
A detailed description of transport end-points is out of scope for
this document. A detailed description of transport end-points is out
of scope for this document but more details can be found in [TRA].
2.2. Naming
In hICN, two name components are defined: the name prefix and the
name suffix. The name prefix is used to identify an application
object, a service or in general an application level source of data
in the network. This is incarnated by a listening socket that binds
to the name prefix. The name suffix is used to index segmented data
within the scope of the name prefix used by the application.
For instance an RTP [RFC3550] source with a given SSRC can be mapped
into a name prefix. Single RTP sequence numbers can be mapped into
name suffixes. For example an HTTP server can listen to a name
prefix to serve HTTP requests. An HTTP reply with large payload with
require the transport layer to segment the application data unit
according to an MTU. Name suffixes are used to index each segment in
the socket stream.
More details about how to use hICN to transport HTTP or RTP will be
given in a different document.
2.2.1. Name prefix
The format of an hICN name prefix is the following:
| 64 bits | 64 bits |
+--------------------------------+-------------------------------+
| routable prefix | data identifier |
+----------------------------------------------------------------+
Figure 2: hICN IPv6 name prefix.
It is composed of a routable IPv6 /64 prefix as per [RFC3587] which
SHOULD be globally routable. The data identifier is encoded in 64
bits. An application can use several identifiers if needed.
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From the description given above, the name prefix is a location
independent name encoded in an IPv6 address.
2.2.2. Name Suffix
The name suffix is used by the transport layer protocol to index
segments. The segment MUST be indexed in the end-points and in the
network with the same suffix. This implies that there is one
transport segment per IP packet and that IP fragmentation is not
allowed. Extension to allow secure fragmentation are possible, such
as [FRA] but they are out of scope for this document. It is up to
the producer end-point to determine how to perform segmentation
depending on the use case. An MTU path discovery protocol for hICN
is out of scope of this document and additional work is required to
extend existing protocols or design new ones.
| 32 bits |
+-----------------------------
| name suffix |
+-----------------------------
Figure 3: hICN name suffix.
2.3. Packet Format
Two protocol data units are defined below: the interest (request) and
the data (reply).
They are composed of a network and transport header. The transport
header is the same for both packet types while the network header is
slightly different.
2.3.1. Interest Packet
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Traffic Class | Flow Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Payload Length | Next Header | Hop Limit |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Source Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Name Prefix +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Interest Packet Header Format
Figure 4: IPv6 interest packet L3 header.
Source Address: 128-bit address of the originator of the packet
(possibly not the end-host but a previous hICN node).
Name Prefix: 128-bit name prefix of the intended service.
2.3.2. Data Packet
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| Traffic Class | Flow Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Payload Length | Next Header | Hop Limit |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Name Prefix +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Destination Address +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Data Packet Header Format
Figure 5: IPv6 data packet L3 header.
Name Prefix: 128-bit name prefix of the intended service.
Source Address: 128-bit address of the destination of the packet
(possibly not the end-host but the next hICN node).
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Port | Destination Port |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name Suffix |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Path Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data | Time |M|A|S|R|S|F| Loss Detection |
| Offset| Scale |A|C|I|S|Y|I| and Recovery |
| | |N|K|G|T|N|N| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Transport header for data and interest packets.
Name Suffix: 32-bit name-suffix of the packet
(possibly not the end-host but a previous hICN node).
Path Label: 32-bit label used to carry an encoding of the path
between the consumer and data responder, be it an
intermediate node or the producer end-point.
Time Scale: 6-bit natural number in the range 1-64 used as a scaling
factor for time calculations. If not null it is used
to scale lifetime.
Manifest: flag to indicate the packet carries a transport manifest
in the payload.
Signature: flag to indicate the packet carries an authentication
header with a signature. Interest packet do not carry
signatures.
Loss Detection: 16-bit natural number used to implement data
and Recovery sequencing on per adjacency basis to detect an
recover losses using the mechanism WLDR described
in {{WLD}}.
Lifetime: 16-bit unsigned integer to carry the packet lifetime in
milliseconds.
Checksum: Updated using RFC 1624.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Port | Destination Port |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name Suffix |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Path Label |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Data | Time |M|A|S|R|S|F| Loss Detection |
| Offset| Scale |A|C|I|S|Y|I| and Recovery |
| | |N|K|G|T|N|N| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Checksum | Lifetime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: Transport header for data and interest packets using UDP
header.
Both transport headers can be used to carry name suffix information.
The following sections describe the components of an hICN node and
the packet processing operations.
2.4. Packet cache
The packet cache is a router local memory used to temporarily store
requests and reply. The simplest incarnation of the packet cache
MUST index packets by full name, i.e. the concatenation of the name
prefix and suffix. Insertion and deletion of packets in the cache is
described below.
2.5. Forwarding
The forwarding path in hICN is composed of two components: the
interest and data path. Requests and replies are processed at the
hICN node in a different way. Both forwarding paths require a packet
cache to be incorporated into the router. The cache is used to
temporarily store requests and replies for a relatively short amount
of time.
By caching a request in an hICN node, the reply can be transmitted
back to the right nodes as the source address field in the interest
contains the interface identifier of the hICN node having transmitted
the request. Replies are optionally cached if needed.
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This means that the interest forwarding path is based on lookups in
the IP FIB just like any other IP packet, with the additional
processing due to a cache lookup to check if the actual reply is
already present in the local cache for expedited reply.
On the other hand, data packet forwarding is similar to label
swapping [RFC3031], being the packet name identifier (prefix plus
suffix) the forwarding label. The next hop for the reply in transit
is indeed selected by using information in a cached matching request.
The name prefix in the packet header is never modified along the path
for both requests and replies, while the locator, i.e. the interface
identifier written in the source or destination address field, for
interest or data packets respectively, is modified at the egress of
the router as reported below.
2.5.1. Interest Path
At the router ingress the incoming interest packet I is parsed to
obtain the name prefix and the name suffix. An exact match look up
is made in the packet cache using the full packet name as key. Based
on the outcome of the lookup the following options are possible:
1. at least one match is found.
1.1. If one match is a data packet D, other matches are ignored,
and D is prepared for transmission by setting D's
destination address with I's source address. D is passed to the
egress to further processing before transmission. For instance
the next-hop MAY be selected by using the router IPv6 FIB
(longest prefix match). The IPv6 FIB lookup MIGHT be saved in
case the next-hop can be derived directly from information
previously derived by processing the incoming interest packet I.
I is eventually dropped.
1.2. There is one or multiple matches and all are interest
packets.
* One matching interest has the same source address and I is
classified as duplicate and further processed as duplicate.
* Matching interest packets have different source addresses and
I is classified as filtered and stored in the cache.
2. a match is not found and I passed to the egress for further
processing to determine the next-hop by using the router IP FIB.
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Notice that the destination address field in the interest packet is
polymorphic as it has two different types based on the data
structured it is looked-up against. It has the type of a location
independent name while used to find a match in the packet cache and
it has an address prefix type to find the next-hop in the IPv6 FIB.
Polymorphism is transparent for the forwarding plane while it has
several implications in the control plane.
Packet Cache
RX +------------+
Interest | | Translation Operation
+---------> Data Hit | IPv6Hdr(Data).DstAddr:= IPv6Hdr(Interest).SrcAddr
TX | + |
Data | | |
<---------+ <----+ |
+------------+
Figure 8: The interest packet hits a matching data packet in the
packet cache.
+----------------+ +--------+
Interest | | | | Egress NIC
+-------> Data Miss +--->+ IP FIB |+----->
| | | | Translation Operation
| Interest Miss | | | IPv6Hdr(Interest).SrcAddr:= NIC.Addr
| | | |
+----------------+ +--------+
Figure 9: The interest packet finds no match in the packet cache and
is processed to find a next-hop.
Same src addr
Packet Cache +-----------+
+--------------+ | Duplicate |
Interest | | +-----^-----+
+-------> Data Miss | |
| Interest Hit +-------------->-+
| | |
+--------------+ |
+-----v-----+
|Filtered |
+-----------+
Different src addr
Figure 10: The interest packet hits an interest packet in the packet
cache.
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2.5.2. Data Path
At the router ingress the incoming data packet D is parsed to obtain
the name prefix and the name suffix. An exact match look up is made
in the packet cache using the full packet name as key. Based on the
outcome of the lookup the following options are possible:
1. one or multiple matching interest packets are found 1.1. The
data packet D is cloned to have as many copies as the number of
matching interests including D. The destination address field of
each copy of D is set with the source address field of each
interest packet. All copies are passed to the egress to further
processing before transmission in order to find each data
packet's next-hop.
2. No matching is an interest packet and the D is dropped.
RX
Data +-----------+
+--------> | Interest |
| Hit |
| + |
+-----------+
|
|
|
| Translation Operation
| +------>
| | IPv6Hdr(Data[1]).DstAddr:=IPv6Hdr(Interest[1]).SrcAddr
| | TX Data[1]
+-----> |
| ...
|
|
| IPv6Hdr(Data[N]).DstAddr:=IPv6Hdr(Interest[N]).SrcAddr
| TX Data[N]
+------>
Figure 11: The data packet hits an interest packet in the packet
cache.
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RX Packet Cache
Data +------------------+ Drop Data
+---------->+ Interest Miss +------>
| OR Data hit |
+------------------+
Figure 12: The data packet is drop in case no interest match is found
in the packet cache.
3. Security
hICN inherits ICN data-centric security model: integrity, data-origin
authenticity and confidentiality are tied to the content rather than
to the channel.
Integrity and data-origin authenticity are provided through a digital
signature computed by the producer and included in each data packet.
Integrity and data-origin authenticity are provided in two ways using
two approaches: the first one based on IP Authenticated Header
[RFC4302] and the second one based on transport manifests. Notice
that the IP AH is not used as an IPv6 extension header as it is
appended after the transport header. However the choice of the IP AH
has been made in order to exploit existing protocol implementations
in the end-points.
When using IP AH, the signature is computed over
o (i)IP or extension header fields either immutable in transit or
that are predictable in value upon arrival at the consumer,
o (ii) the AH header with the signature field set to zero. We
recall that in hICN the destination header field is not immutable
nor predictable and must be set to zero for the signature
computation. We also point out the AH in placed after the TCP
header in order to prevent any kind of filtering from network
devices such as middleboxes.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Next Header | Payload Len | ValidAlg | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ /
/ KeyID /
/ /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ /
/ Signature /
/ /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: The IP authentication header appended after the transport
header to carry packet signatures.
ValidAlg: 8-bit index to indicate which validation algorithm
must be used to verify the signature.
Timestamp: 64-bit time stamp that indicates the validity of the
signature.
KeyID: 256-bit key identifier.
Signature: Variable length field that carries the cryptographic
signature of the security envelope.
It is 128 bytes for RSA-1024, 256 bytes for RSA-2048,
56 bytes for EDCSA 192, 72 bytes for ECDSA 256.
The transport manifest is a L4 entity computed at the producer which
contains the list of names of a group of data packets to convey to
the consumer. hICN cryptographic hashes of data packets are then
computed instead of signatures. The hashes are computed on immutable
fields as explained above when using the IP AH. Moreover, the
manifest must be signed to guarantee a level of security equivalent
to packet-wise signatures. When the producer uses the manifest data
packets do not carry the AH which is carried by the transport
manifest only.
hICN is oblivious of the trust model adopted by consumers and works
with any of the existing proposals.
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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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Version| MType |HashAlg|NextStr| Flags |NumberOfEntries|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+ +
| |
+ Prefix +
| |
+ +
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name-suffix[1] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hash Value[1] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
. . .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Name-suffix[NumberOfEntries] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hash Value [NumberOfEntries] |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 14: The transport manifest, generated by the producer end-
point for the consumer end-point, contains names, integrity hashes
and is signed with the producer end-point private key
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Version: 8-bit index to indicate which validation algorithm
must be used to verify the signature.
MType: 64-bit time stamp that indicates the validity of the
signature.
HashAlg: 256-bit key identifier.
NextStr: Encode an operator use to predict the name-suffix
sequence
Flags: Flags.
NumberOfEntries: 8-bit field that encodes the number of packets indexed
in the manifest.
Name-prefix: 128-bit field carrying the name-prefix common to all
packets indexed in the manifest.
Name-suffix: 32-bit field carrying the name-suffix.
Hash-value: 256-bit field carrying the SHA-256 hash of the packet
security envelop.
4. The End-host model and End-to-End considerations
In hICN the end-host model is very similar to a regular IPv6 end-host
with some extensions. An end-host is capable of opening consumer and
producer transport end-points, one to receive data and one to send
data under a given name prefix. The end-host continues to identify
interfaces using IPv6 addresses (locators or routing locators, RLOCs,
using LISP terminology), just like any IPv6 router. In addition to
that, transport end-points bind to location-independent names,
similar to LISP end-point identifiers (EIDs). However, instead of
using name prefixes to identify end-hosts only, in hICN a name prefix
is used to identify a data source.
There is an analogy between IPv6 multicast and the hICN data
forwarding path for one-to-many communications, as the IPv6 multicast
group address identifies data that group members receive from a
single sender. Notice that in hICN a data packet transmission stores
the identifiers in the source address field while in IPv6 multicast
it is stored in the destination address field.
Theres is also an analogy between IPv6 anycast and the hICN interest
forwarding path, where multiple interfaces make use of the same IPv6
(anycast) address. Multiple instances of the same applications can
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then run at different end-points to eventually reply to the same
request.
An hICN network node behaves as an end-host consumer end-point for
the upstream producer end-point as all replies are forced to flow
back to the same hICN that transmitted the requests. An hICN network
node may be able to reply to a request on behalf of a end-point
producer, in that case that hICN node behaves as an end-host for the
consumer end-point.
5. IANA Considerations
There are no IANA considerations in this specification.
6. Acknowledgements
The authors would like to thank David Ward, David Oran, Paul Polakos,
Mark Townsley, Mauro Sardara and Alberto Compagno for suggestions on
how to improve the architecture and the current document.
7. References
7.1. 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>.
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/info/rfc3031>.
[RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V.
Jacobson, "RTP: A Transport Protocol for Real-Time
Applications", STD 64, RFC 3550, DOI 10.17487/RFC3550,
July 2003, <https://www.rfc-editor.org/info/rfc3550>.
[RFC3587] Hinden, R., Deering, S., and E. Nordmark, "IPv6 Global
Unicast Address Format", RFC 3587, DOI 10.17487/RFC3587,
August 2003, <https://www.rfc-editor.org/info/rfc3587>.
[RFC4302] Kent, S., "IP Authentication Header", RFC 4302,
DOI 10.17487/RFC4302, December 2005,
<https://www.rfc-editor.org/info/rfc4302>.
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[RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
Locator/ID Separation Protocol (LISP)", RFC 6830,
DOI 10.17487/RFC6830, January 2013,
<https://www.rfc-editor.org/info/rfc6830>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
[RFC8569] Mosko, M., Solis, I., and C. Wood, "Content-Centric
Networking (CCNx) Semantics", RFC 8569,
DOI 10.17487/RFC8569, July 2019,
<https://www.rfc-editor.org/info/rfc8569>.
[RFC8609] Mosko, M., Solis, I., and C. Wood, "Content-Centric
Networking (CCNx) Messages in TLV Format", RFC 8609,
DOI 10.17487/RFC8609, July 2019,
<https://www.rfc-editor.org/info/rfc8609>.
7.2. Informative References
[CCN] Jacobson, V., Smetters, D., Thornton, J., Plass, M.,
Briggs, N., and R. Braynard, "Networking named content",
Proceedings of the 5th international conference on
Emerging networking experiments and technologies -
CoNEXT '09, DOI 10.1145/1658939.1658941, 2009.
[FRA] Mosko, M. and C. Wood, "Secure Fragmentation for Content
Centric Networking", 2015 IEEE 12th International
Conference on Mobile Ad Hoc and Sensor Systems,
DOI 10.1109/mass.2015.51, October 2015.
[MAN] Baugher, M., Davie, B., Narayanan, A., and D. Oran, "Self-
verifying names for read-only named data", 2012
Proceedings IEEE INFOCOM Workshops,
DOI 10.1109/infcomw.2012.6193505, March 2012.
[MIR] Garcia-Luna-Aceves, J., Martinez-Castillo, J., and R.
Menchaca-Mendez, "Routing to Multi-Instantiated
Destinations: Principles, Practice, and Applications",
IEEE Transactions on Mobile Computing Vol. 17, pp.
1696-1709, DOI 10.1109/tmc.2017.2734658, July 2018.
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[NDN] Zhang, L., Afanasyev, A., Burke, J., Jacobson, V., claffy,
k., Crowley, P., Papadopoulos, C., Wang, L., and B. Zhang,
"Named data networking", ACM SIGCOMM Computer
Communication Review Vol. 44, pp. 66-73,
DOI 10.1145/2656877.2656887, July 2014.
[RAQ] Carofiglio, G., Gallo, M., Muscariello, L., Papalini, M.,
and S. Wang, "Optimal multipath congestion control and
request forwarding in Information-Centric Networks", 2013
21st IEEE International Conference on Network
Protocols (ICNP), DOI 10.1109/icnp.2013.6733576, October
2013.
[TRA] Sardara, M., Muscariello, L., and A. Compagno, "A
transport layer and socket API for (h)ICN", Proceedings of
the 5th ACM Conference on Information-Centric Networking -
ICN '18, DOI 10.1145/3267955.3267972, 2018.
[WLD] Carofiglio, G., Muscariello, L., Papalini, M., Rozhnova,
N., and X. Zeng, "Leveraging ICN In-network Control for
Loss Detection and Recovery in Wireless Mobile networks",
Proceedings of the 2016 conference on 3rd ACM Conference
on Information-Centric Networking - ACM-ICN '16,
DOI 10.1145/2984356.2984361, 2016.
Authors' Addresses
Luca Muscariello
Cisco Systems Inc.
Email: lumuscar@cisco.com
Giovanna Carofiglio
Cisco Systems Inc.
Email: gcarofig@cisco.com
Jordan Auge
Cisco Systems Inc.
Email: augjorda@cisco.com
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Michele Papalini
Cisco Systems Inc.
Email: mpapal@cisco.com
Muscariello, et al. Expires May 2, 2020 [Page 23]