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Re: [WG-BB] Study Report: CATV assignment guidline
> | thought that cable modems are placed in every head end. I think I saw
> | somewhere that average home passes per head end is 500. Please correct me
> | if I am wrong.
Yes, I think so it is usually 500〜1,000 per one downstream channel
using legacy CMTS which modulate by QPSK/S-CDMA/etc. There downstream
bandwidth per one port are 8Mbps〜10Mbps.
legacy CMTS: LANcity, Terayon, Com21, Pioneer, etc ...
=> They are hardly installed as new facilities.
It is better to take care, since the word "head end" had some meanings.
... CMTS chassis / all CMTS in the room / machine room itself / etc
> They say it is 1,500 to 2,000. I also want the input from
> Operators themselves, please.
I think they said that number supposing DOCSIS system. DOCSIS system
currently have been installed in almost operators. It usually has been
operating on 64QAM, 30Mbps per one downstream port.
DOCSIS: Data Over Cable Service Interface Specification
=> current standard of cable data communication system
Since there price are very low by the effect of
standardization, the operators of many countries have
also installed them as new facilities.
DOCSIS CMTS of Cisco ( 85% current marcket share ) are equipped
with multiple (〜16 max) downstream ports per one chassis.
Therefore, one CMTS connects much more terminal modems.
Regards,
-- ashida
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