[c-nsp] IOS Recommendation | 7600/RSP720-3CXL

[Matt Addison]

> Have found the least bugs in SRD1, but non-cisco bgp neighbors
> sometimes require the use of hidden command "neighbor x.x.x.x dont-
> capability-negotiate" or the session won't restore.

We're also quite happy with SRD1. Early SRBx had a few issues with OSPF,
and SSO/ISSU with static routes up until B4 or so.

SRC1 (and everything up to it presumably) have some bugs in the how PPP
(at least on T1/DS3, not sure about POS) gets put on the fabric which
affects interop with non-Cisco PPP implementations, I hear that fix also
made it into SRC2 but we migrated to SRD1 because at that time SRC2 was
still a month or two out.

~Matt