Chapter3. Configuring 3Com VCX IP Telecommuting Module
Seeappendix C, Lists of Reserved Ports, ICMP Types and Codes, and Internet Protocols, for more information on
netmasks.
Name queries in 3Com VCX IP Telecommuting Module
ATelecommuting Module should be as independent of other computers as possible. At the same time, the person
whochanges the configuration of the Telecommuting Module may want to use names for the computers instead of
IPaddresses. Also, the SIP module needs to look up names of SIP domains. This makes it necessary to use a DNS
(nameserver) for SIP requests.
Thereare three instances when 3Com VCX IP Telecommuting Module uses a DNS server:
•Whenit receives a SIP request for a SIP domain.
Theresults of these DNS queries are stored for a short while in the Telecommuting Module.
•Whenyou change names/IP addresses and save the page.
Theresults of these DNS queries are stored in the Telecommuting Module.
•Whenyou click on Look up all IP addresses again.
Theresults of these DNS queries are stored in the Telecommuting Module.
3ComVCX IP Telecommuting Module is dependent of a working name server for the SIP functions. However, it
doesn’tautomatically look up IP addresses in the configuration, which makes it necessary to click on Look up all
IPaddresses again every time a computer changes its IP address.
Whenyou enter IP addresses in the Telecommuting Module, they are not updated automatically. If you change a
name/IPaddress in a row, the row is updated when you click on Save, switch to another page of the Telecommuting
Moduleuser interface, or click on Look up all IP addresses again.
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