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DOCSIS 2.5 modem

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DOCSIS 2.5 modem

I've been told that there are some 2.0 modems out there that actually perform channel bonding on the downstreams. They are unofficially referred to as 2.5 modems.

Does anyone know if they use the same RCP TLVs as DOCSIS 3.0 modems? Or do they have some other way of sending RCP info?

don't think so

a 2.0 modem has a single receiver and a single transmitter, I do not know of any 2.0 modem that would have more than a single. it wouldn't be able to be certified 2.0

In fact docsis 2.5 are docsis

In fact docsis 2.5 are docsis 3 for downstream and docsis 2 for upstream.
The only constraint is to validate a configuration of your cmts that synchronise your 3 dowstreams.
It depends of your cmts vendor and type. Also you might have problems if your downstream frequencies are too far each over

Ah, Interesting. And I assume

Ah, Interesting. And I assume the docsis 2.5 downstream registration request includes Receive Channel Profiles that meet the 3.0 specs as described in the MULPI spec?

Why bother ?

Why bother ?

DOCSIS 3.0 modems are cheap and a much safer option

I don't want to own one, I

I don't want to own one, I just need to understand the different modems that are out there an how they behave. It's for my job.

What kind of job?

What kind of job? Are you the Indiana Jones of digital archeology? I'm almost 18 years in this business and DOCSIS 2.0b was so quick in and out that it's sharing a flat with its friend HD-MAC and DOCSIS 1.0+


DOCSIS 2.0b was in the

DOCSIS 2.0b was in the roadmap for broadcom chipsets.
Many cable modem manufacturers (Netgear, Ambit, Ubee...) have included the chipset for limited price to challenge XDSL speeds.
Of course DOCSIS 3.0 modems are cheap and yes, it is time to swap such modems because of the lack of quality regarding the upstream part.
Also configuration can be complex (depending CMTS vendor) and you have to track modems and area where all DS are not synchronized.