Routing WG: Explicit Routing (ER)

Some members and gigaPoPs have described needs for routing behavior more sophisticated than the current technique of forwarding to a next-hop router based on destination IP address. The capability of making forwarding decisions incorporating source information — e.g., source IP address, input interface on a router or switch, or a label/tag in the packet — is a requirement of any solution to this problem. The solution must also address the "fish problem" (need a reference): there must be a mechanism for a packet to traverse a router en route to an egress port on another router, even when this router has a "better" route to the destination. For example, the site originating the packet may be disallowed by policy from transiting a network which would offer a "better" path (i.e., fewer hops, greater bandwidth, lower latency, etc.).

Several router manufacturers are developing technologies that may provide a solution to this problem. The I2rwg monitors these developments, offers critical and constructive feedback, and will evaluate and test these technologies when appropriate. When a suitable solution is available, the I2rwg will provide deployment advice and assistance, as desired by backbone, gigaPoP, and site operators.

Milestones

Manufacturer status reports at Jan 2001 Jt Techs meeting. 28-31 Jan 2001
Evaluate and test potential solutions. unscheduled