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Cisco WAN Manager User’s Guide
Version 10.5, Part Number 78-12945-01 Rev. D0, August 2003
Chapter11 CWM to CWM Communications
CWMGateway Process
CWMGateway Process
The CWMGateway process provides a communications gateway for CMW workstations. Processes
owned by one CWM workstation can commun ica te wit h pro cess es owne d b y anot her CWM wo rks ta tion
using the CWMGateway process.
CWM workstations within th e same CWM domain com mu n icate with other CWM work stations by
transferring information between t he CW MGateway processes of each CWM wo r kst ati on . Th e
communication between CWM workstations is set up transparently by the CWMGateway processes in
each CWM workstation.
CWM core processes communicate w ith the CWMGateway process of the CWM workstation to request
information from and to send information to another CWM workstation.
CWMGateway Functionality
With the use of the CWMGateway Pro cess , CW M to CWM communications al lows C W M to h ave th e
following functional ity :
•CWM can determine, without the help of the managed network, the presence of other managing
CWM servers. This is achieved by hav ing IP c on n ect ivit y be tw een a ll CW M workstations.
Note Loss of IP connectivity means that the P r ima ry and Secondary CWMs are no t a bl e t o com municate
through sending or receiving network information, and are not able to ping each other.
•CWM workstations can communicate with other (remote) CWM workstations.
•If a Primary CWM workstation were to be sh ut do wn , anot he r CWM work sta t ion wou ld beco me th e
new Primary CWM.
•If failure occurs, suc h as a loss of commun ication, it can be detec ted and recovered pred ictably and
reliably.
Apart from the redundancy asp ect , one addi t ion al be nef i t of the CWM g ateway is the ability for mult ip le
CWM workstations to share U ser Data, as well as maintai n synchronization with the n etwork. The CWM
Gateway process maintains consistency of user data across the CWM domain, while the proprietary
Robust Trap mechanism and SNMP maintain the CWM database consistent with the network data.
Network Data is defined as data that originates in the network and is communicated to the CWM
workstation(s) by means of the proprietary Robust Trap mechanism or by SNMP, depending on the
network element concerned. An exam ple of network data is a change i n ala rm s ta tu s f or a u s er p or t or
access line.
User Data is information that is supplied by a CWM user, or by an external OSS, and which cannot be
stored in a network element an d was therefore not visible to other C W M wo r ks tat io ns prior to Release
10. Examples of User Data include connection tem plate s, Servic e Clas s Templates, SNMP com mu nity
strings, and the uniq u e n o de IDs generated by CW M d uring the network di sc ove ry process.
With the CWM gateway function , User Data is propagated between the CWM workstat ions in a domain,
thereby maintaining consistency. The Primary CW M acts as an arbitrator to prevent contention be tween
CWM workstations for the same e lement of User Data. This mean s, f o r examp l e, t hat if a user on one
CWM workstation wants to modify a parti c ular con nect ion t empl a te, the Co nne cti on Template Manager
process on that CWM workstation m ust r eq ues t the Primary CWM workstation t o l oc k t ha t r eso ur ce to
prevent concurrent modification by two users.