I2RS use case for IPv6 transitionChina MobileUnit2, 28 Xuanwumenxi Ave,Xuanwu DistrictBeijing 100053Chinaliudapeng@chinamobile.com
I2RS
This document discusses the use cases of I2RS in IPv4/IPv6 transition scenario.
I2RS working group is chartered to define an interface to the routing
system. This interface can be used to read topology and forwarding
information of the routing system. This document discusses the
use cases of I2RS in IPv4/IPv6 transition scenario.
RIB: Routing Information Base
I2RS: Interface to Routing System
There are several different ways for IPv4/IPv6 transition. For example,
dual-stack is one popular technology to enable IPv4 to IPv6 transition.
In dual-stack network, every router has both IPv4 and IPv6 IP stack
running on it. The IPv4 and IPv6 protocol stack running on the
dual-stack router normally work independently from each other
although they share the same physical resources in the dual-stack
router(CPU,memory etc). There are two different views of the dual-stack network
from the IPv4 or IPv6 perspective. There are different set of routing information
base for IPv4 and IPv6. In most cases, the IPv4 and IPv6 network need to have
the same topology and forwarding state since they normally serves for the same
dusal-stack host.
Figure 1. IPv4/IPv6 Dual-stack network for IPv4/IPv6 transition
It is a big challenge for the operators to operate dual-stack network, there are
several reasons:
1. The network operation and management team may not familiar with IPv6. They
have to learn new knowledge and new tools for IPv6.
2. There are two separate domains of the IPv4 and IPv6 network, the trouble shooting
will become much more complex than single stack network.
3. Since the IPv4 and IPv6 stack share a single physical router, the problem of one
protocol stack may spread to the other stack.
With I2RS, it can help the network operator to maintain a consistent view of both the IPv4 and
IPv6 network in real time. The network operator can even configure the IPv6 network based on
the existing IPv4 network and make the IPv4 network and the IPv6 have the same topology and
forwarding state. This will reduce the complexity of operation and management and help the
network operator discovery the in-consistent between the IPv4 and IPv6 network quickly.
In IPv4 and IPv6 translation scenario, the IPv4/IPv6 network's packets will
be translated in to IPv4/IPv6 network's packets and vice versa. It is
difficult for the network management system to get a consistent view of the
translated network.
Figure 2. IPv4/IPv6 translation network for IPv4/IPv6 transition
It is difficult for the current network management system to get IPv4 and
IPv6 network topology and routing information simultaneously. With I2RS,
it can provide a flexible way to get both IPv4 and IPv6 network topology
and other information, hence it could be very useful for trouble shooting
and network management.
From the above use case, the requirements for I2RS are:
1. I2RS interface should support both IPv4 and IPv6. It should be able
to read both IPv4 and IPv6 routing information in a timely manner.
2. I2RS interface should have enough security mechanism to protect the
data that read from the routing information base.
3. I2RS interface should have data consistent protection mechanism to
protect the data in the routing information base.
4. I2RS interface should allow injection of routing polices to the
routing forwarding table.
Routing information is very critical and sensitive information for
the operators. I2RS should provide strong security mechanism
to protect the routing information that it could not be accessed
by the un-authorised users. It should also protect the security and
integrity protection of the routing data.
No IANA action is required.TBDInterface to the Routing System Problem Statement