Editing Cable modem (section)

==Cable modem flap==
Cable modems can have a problem known in industry jargon as "flap" or "flapping".<ref>{{cite web|url=http://www.cisco.com/c/en/us/td/docs/cable/cmts/feature/guide/cmtsfg/ufg_flap.pdf|title=Flap List Troubleshooting for the Cisco CMTS|publisher=Cisco|access-date=26 July 2016}}</ref> A modem flap is when the connection by the modem to the head-end has been dropped (gone offline) and then comes back online. The time offline or rate of flap is not typically recorded, only the incidence. While this is a common occurrence and usually unnoticed, if a modem's flap is extremely high, these disconnects can cause service to be disrupted. If there are usability problems due to flap the typical cause is a defective modem or very high amounts of traffic on the service provider's network (upstream utilization too high).<ref>{{cite web|url=http://www.dslreports.com/forum/remark,2507788 |title=Cable modem flapping.. - RCN &#124; DSLReports Forums |website=Dslreports.com |access-date=2016-08-03}}</ref> Types of flap include reinsertions, hits and misses, and power adjustments.<ref>{{cite web|url=http://www.cisco.com/en/US/docs/ios/cable/configuration/guide/cmts_flaplst_trbsh.html |title=CMTS Troubleshooting and Network Management Features Configuration Guide |website=Cisco.com |date=2016-01-27 |access-date=2016-08-03}}</ref>