Cisco DNCS System Release 2.7 3.7 4.2 テクニカルリファレンス

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Operations Alert Bulletin 
Limitations on Headend IP Addresses 
for Set-Tops in DOCSIS Mode 
Engineers at Cable Television Laboratories, Inc. (CableLabs®) have reserved the IP address for diagnostic purposes for cable modems. Because 
CableLabs did not specify a subnet mask, Cisco chose, the Internet 
standard for a Class C IP address. 
If a headend server is assigned an IP address in the subnet, then 
neither the cable modem nor the set-top itself will be able to communicate with the 
headend server, resulting in possible service outages. Examples of headend servers 
include the Digital Network Control System (DNCS), the video-on-demand (VOD) 
server, the Dynamic Host Configuration Protocol (DHCP) server, and the Trivial File 
Transfer Protocol (TFTP) server. 
System operators must avoid assigning an IP address in the subnet 
to any headend server. Any headend servers that currently have an IP address in the subnet must be assigned a new IP address. Furthermore, no set-top 
or cable modem can be assigned an IP address in the subnet, either. 
Note:  Set-tops that operate in DAVIC mode are not affected by this limitation. 

テクニカルリファレンス Cisco DNCS System Release 2.7 3.7 4.2 の仕様概要

  • ページ 1Operations Alert Bulletin Limitations on Headend IP Addresses for Set-Tops in DOCSIS Mode Background Engineers at Cable Television Laboratories, Inc....
  • ページ 2About This Bulletin About This Bulletin Audience This document is intended for system operators and network administrators of Cisco’s Digital...
  • ページ 3
  • ページ 4For More Information If You Have Questions If you have technical questions, call Cisco Services for assistance. Follow the menu...