[c-nsp] interface between data- and control-plane on Cisco platforms

[Martin T]

Hi,

as I understand, Juniper equipment(at least M and MX series) use
100BASE-TX or 1000BASE-T(depends on routing-engine model) Ethernet
interface between the data- and control-plane with IPv4 addresses from
10.0.0.0/8 and 128.0.0.0/2 and IPv6 addresses from fe80::/64 and
fec0::/64 networks configured to those interfaces. Of course, those
networks are in a separate VRF's and physically the connection is
probably part of large fixed connector to back-plane. This allows
UDP/IP and TCP/IP based connections between data- and control-plane.
For example IPv4 connections:


> show system connections inet show-routing-instances | match __juniper_private1__
tcp4       0      0  128.0.0.1.6234
128.0.0.2.44033                               __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.1.6021
128.0.0.2.44032                               __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.9000
128.0.0.4.55154                               __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.55154
128.0.0.4.9000                                __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.9000
128.0.0.4.50005                               __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.50005
128.0.0.4.9000                                __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.9000
128.0.0.4.49964                               __juniper_private1__
ESTABLISHED
tcp4       0      0  128.0.0.4.49964
128.0.0.4.9000                                __juniper_private1__
ESTABLISHED
tcp4       0      0  *.9000                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.7000                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6151                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6161                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.31343                                       *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.31341                                       *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6154                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6153                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6152                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6156                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.666                                         *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6021                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.38                                          *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.10798                                       *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6011                                        *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.514                                         *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.513                                         *.*
                                          __juniper_private1__
LISTEN
tcp4       0      0  *.6234                                        *.*
                                          __juniper_private1__
LISTEN
udp4       0      0  128.0.0.1.123                                 *.*
                                          __juniper_private1__
udp4       0      0  *.31342                                       *.*
                                          __juniper_private1__
udp4       0      0  *.31340                                       *.*
                                          __juniper_private1__
udp4       0      0  *.6123                                        *.*
                                          __juniper_private1__
udp4       0      0  *.6333                                        *.*
                                          __juniper_private1__


Please correct me if I'm wrong.

However, what kind of interface does Cisco use to connect control
plane with data plane? I mean there has to be some interface/bus which
is used to sync RIB with FIB or ARP database with Adjacency Database
on platforms which support CEF. Is it some sort of proprietary bus on
most platforms? I guess while 1800 series ISR routers, Cisco 4500
series SUP and Cisco 3750 series switches all have the "control-plane"
interface present, then actually different underlying technologies
might be used for this interface/bus?



regards,
Martin