NOC Tools continued; For example these tools can be used to check the status of certain aspects of the Network, i.e. RF issues on a Cisco Ubr (Headend), Load balancing issues in a Network market, server issues (i.e. DHCP, Gateway) and routing issues, to list a few examples. Also in some cases these sets of tools can be used to access information on a specific customers Cable Modem status on the Network (i.e. db check, flap list history) or maybe even reset the Cable Modem.
The names and functions of these tools can vary due to many variables such as, the type of Network (i.e. Broadband/ADSL ect) , wether or not the tools are propietary to that I.S.P. and the type of equipement used on the Network. A list of commonly used applications/tools that some I.S.P.'s use are MRTG, NMAP's and NDSOFTWARE.
There are basically 2 classes of Cable Modems, DOCSIS and non DOCSIS. Of course the main majority of Modems and Broadband Networks use/adhere to the DOCSIS standard but this doesnt always mean that DOCSIS is better. It just simply means a few years back a whole Bunch of big industry players (companies) sat down to come up with a standard they would all adhere to.
A few companies chose not only to manufacture equipement that would adhere to the DOCSIS standard but also develop and deploy their own Broadband technology standards at the same time, a perfect example of this is Com21. You cannot for example put a non DOCSIS Cable Modem on a DOCSIS Broadband Network and have them operate with each other.
Thus if you were going to have a Network of customers with non-DOCSIS Cable Modems, you would have to have that same technology the Modems are using on your Network Systems (NOC). For example Broadband Cable Networks that use non-DOCSIS Com21 Cable Modems have to use a Com21 Comcontroller for their headend to manage the Cable Modems. They could not for example have a Cisco Ubr as their headend.
Com21 Cable Modems aquire a signal from what is called a ComController and a DOCSIS Cable Modem aquires it signal from what is called a UBR which stands for (Universal Broadcast Router).
Sounds confusing, its ok, basically the differance is simple. Com21 the company basically has its own (proprietary) way of running a Cable Network. Where as the others have conformed to a Industry standard called DOCSIS.
Which one is better, Well thats gonna depend on who you ask. DOCSIS is obviously gonna win in the respect of flexiblity in working with a wide range of vendors broadband technolgies and products. Does this mean its superior in performance?, well since I'm not working in a Broadband NOC...YET! I'm not gonna try to pan myself off as a expert. But heres my 2 cents anyway... From my experience and what I have heard Com21 is fantastic in alot of technical areas and performance. DOCSIS at the same time has alot of technical areas it could win out on. To put it simple think of Com21 as Macintosh.
Here is a list of commonly seen acronyms, abreviations and what they are.
Headend: Central distribution point for a CATV system. Video signals are received here from satellites and maybe other sources, frequency converted to the appropriate channels, combined with locally originated signals, and rebroadcast onto the HFC plant. The headend is where the CMTS is normally located.
CMTS: Cable Modem Termination System. Central device for connecting the cable TV network to a data network like the internet. Normally placed in the headend of the cable TV system.
DOCSIS: Data Over Cable Service Interface Specification. The dominating cable modem standard. Defines technical specifications for both cable modem and CMTS.
HFC: Hybrid fiber-coaxial (cable network). Older CATV systems were provisioned using only coaxial cable. Modern systems use fiber transport from the headend to an optical node located in the neighborhood to reduce system noise. Coaxial cable runs from the node to the subscriber. The fiber plant is generally a star configuration with all optical node fibers terminating at a headend. The coaxial cable part of the system is generally a trunk-and-branch configuration.
MCNS: Multimedia Cable Network System Partners Ltd. The consortium behind the DOCSIS standard for cable modems.
CPE: Customer Premises Equipment. Used to describe the PC and/or other equipment, that the customer may want to connect to the cable modem.
Ranging: The process of automatically adjusting transmit levels and time offsets of individual modems, in order to make sure the bursts coming from different modems line up in the right timeslots and are received at the same power level at the CMTS.
Upstream: The data flowing from the CM to the CMTS.
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