A-5
Cisco WAN Manager User’s Guide
Version 10.5, Part Number 78-12945-01 Rev. D0, August 2003
AppendixA Internet Connectivity Functional Description
IP Host
Once the IPATM interface on every MGX 8850 Relea se 2 is hooked to the IP layer of VxWorks TCP/IP
stack and every SVC has been estab li s he d be tw een I PATM interface and route rs, full connectivity will
exist between all MGX 8850 Release 2 nodes t hrough all rout ers. Thi s commun icati on path h as also been
relayed to the IP host/workstati on usin g a rout ing protoc ol suc h as RIP. The IP host/workstati on will no w
know, via a IP route, which router will accept data for each MGX 8850 Release 2.
Note If the IP host/workstation does not support the routing protocols used by the routers, the IP routes for
each MGX 8850 Release 2 will have to be manually added on the CWM workstation.
All that remains for the I P host to do is to determin e the IP address for each IPATM interface with whi ch
it wants to establish TCP /IP co m mu nication. This can be as si m p le as manually entering these IP
addresses into the host’s host table, or as complex as dynamically determining these IP addresses via
another protocol su ch a s ILMI. In either cas e it is assumed that the IP host/workstation knows the IP
addresses of the IPATM interfaces for the remainder o f th is ch ap ter.
FigureA-5 shows the complete IP data-path between the MGX 8850 Release 2 and the IP
host/workstation. The IP Cloud s ig ni fies an IP ne tw or k an d can b e a s s i mpl e a s a directly attached
ethernet or as complex as a multi-hop, multi-interface type network. Router #1 and Router #2 may or
may not be part of the same IP Cloud.
FigureA-5 IP Connectivity Between MGX 8850 Release 2 and IP workstation
Putting It All Together
It is the job of the IP host/w or k s ta tio n to initiate the IP communic ation to the MGX 8850 Relea se 2 by
sending IP data addressed to th e I PATM interface of the MG X 88 5 0 Re lea se 2 to the correct router.
Once received by the router, the I P address of the destinatio n of the data (MGX 8850 Release 2) is looked
up in the router’s IP route table. Because the IP address of the MGX 8850 Release 2 has been previously
added to this interfaces rou te tab l e, the data is given to the ATM interface driver. There , a map table
39164
Telnet
Client/server API (e.g. Sockets)
TCP UDP
IP
IPATM
interface
Router #1
Router #n
S
I
G
A
P
I
FTP
MGX 8850 R2
SV+
SVC
SVC
TimeOfDay
IP
cloud
IP
cloud
IP host/
workstation
IP host/
workstation