Cisco Headend System Release 2.5 Technical References

Character Restrictions with System 
Releases 2.5/3.5 and 4.0 

 

Prior to the introduction of System Release (SR) 2.5/3.5 and SR 4.0, code version 
table (CVT) download files were managed by the operating system manager (OSM) 
processes of the Digital Network Control System (DNCS). As part of the move to SR 
2.5/3.5 and SR 4.0, these files are now managed by the broadcast file system (BFS) 
processes. One of the consequences of CVT download files being managed by the 
BFS processes is that certain characters that may have been allowed for file-naming 
purposes under the OSM processes are not allowed under the BFS processes. System 
operators who configure download files that use these restricted characters in the file 
name will find that Digital Home Communications Terminals (DHCTs) will not 
download new or existing code. 

 

This technical bulletin describes the impact of the use of special, restricted characters 
on the CVT download process, lists the restricted characters, and provides system 
operators with instructions on what to do should they inadvertently name a CVT 
download file using a restricted character. 

 
 

This technical bulletin is written for system operators who use Cisco's Digital 
Broadband Delivery System (DBDS). Cisco engineers who help system operators 
manage their systems may also find this technical bulletin to be useful.