Telco Glossary

A large part of dealing with telco carriers is knowing the lingo. They are usually understaffed and overworked (or would like you to believe so even if it doesn’t happen to be the case at any point in time) so they tend to use a lot of acronyms to speed things along in shorthand. Understanding what they’re saying is one of the most important things.

  • Hardware:
    • CSU
    • DACS
    • DSX
    • DSU
    • IA
    • Lightspan
    • MUX
    • NIE/NI/NIU/NEI
    • OCU
    • SMJK: Smartjack. A smartjack is a type of network interface that is loopable.
  • Software
    • HPOV: HP’s OpenView.
    • EOTS: Eye of the Storm. A proactive monitor that checks for errors accruing on circuits and warns when enough errors are noted. This is helpful for isolating trouble on a circuit as it will detect problems even when the circuit does not actually drop.
    • IOS
  • Concepts
    • A-end/Z-end
    • ATM
    • BGP: Border Gateway Protocal. This is a routing protocol.
    • CER: Customer Edge Router.
    • DBU: Dial back up. Basically, if the main circuit goes down, the remote router will connect to the host via means of a 56k modem or ISDN circuit. This is a fairly inexpensive means of ensuring that your business is not impacted when a circuit outage occurs. (It won’t help you if the local phone lines go down due to a cable cut or accident knocking down poles, but if it’s a circuit issue beyond the local CO, you’ll probably be able to use the phone line successfully as a backup.)I’ve never understood why so many customers don’t plan ahead for outages (!@#$ happens, after all) and have a DBU system in place.
    • demarc/demarcation point: The end of telco responsibility. The demarcation point is where an imaginary line is drawn; on one end of that line, telco must fix any problems. On the other end of the line, the customer is responsible for fixing any problems. This is usually placed at the network interface, and any inside wiring and customer premise equipment are the customer’s responsibility.If telco can test clean to the NI and sees errors from the site, they will often refuse to dispatch out to test physically onsite, or delay the dispatch as it will be considered a “demand” dispatch to prove through the demarc. Note that just because they test clean to the NI does not mean it’s not defective; it just means that there is not likely to be a physical circuit issue leading to the NI.
    • DLCI
    • FR: Frame Relay.
    • IMA
    • IPFR/PIP: IP-enabled Frame Relay / Private IP service. This is frame relay service, without the hassle of managing PVCs with DLCI to DLCI mapping. Instead, the telco carrier provides BGP advertisements and nodes can communicate to each other through the BGP routes. This is especially helpful for large networks where adding and removing nodes can be a large hassle managing tons of PVCs.
    • LEC: Local Exchange Carrier.
    • loop
    • OOB: Out of band. This is typically a modem (internal or external) connected to a router for means of remote management when the circuit is down. Some customers use this in place of dial backup, allowing remote verification of power when an outage occurs. It is also highly recommended that an OOB system be put into place for core routers; being able to manage the core routers and recover from a configuration mistake is of critical importance.
    • PER: Provider Edge Router.
    • P2P/PTP: Point-to-point. A physical circuit connected between two routers.
    • PVC: Private virtual circuit. This is a mapping in the frame relay cloud between two DLCIs, establishing a “virtual” circuit between the two circuits.
    • xcon/cross connect
  • Patterns:
    • DDS 1-4
    • 2047
    • Hex 40
    • 1 in 8
    • 2 in 8
    • 3 in 24
    • 55 Octect
    • Quasi/QRSS
    • all 0’s
    • all 1’s
  • Telco groups
    • Chronic
    • DATEC: DATEC is the group that works chronic tickets for AT&T.
    • PLG: Physical Layer Group. I’ve seen this one primarily used by Sprint/Nextel for their physical layer troubleshooting group.
    • Proactive: Most telcos have a proactive group where, if the customer pays for the service, they will open a ticket when they see a trouble on the circuit and inform the customer (or the customer-designated contact). Sometimes they’ll open a ticket after you’ve already called one in, or sometimes they’ll beat you to the punch. (Sometimes they won’t even notice it’s down.) If the customer doesn’t pay for proactive service, however, it’s up to them (or you, if you do the monitoring for them) to open tickets with telco.
  • Ticket acronyms:
    • 1st AM: Exactly what this means varies from carrier to carrier, but if a site is not physically manned 24/7, dispatches are usually scheduled for “first AM”. This tends to range from 0800 to 1000 local time.
    • ASC/all 1s/AIS: Abnormal station code, or alarm indication signal. Basically, telco is getting no response from the remote site. This usually indicates a loss of power or connectivity at the site (if the cable was unplugged, for example). Note that you’ll want to verify what the telco is seeing ASC from; a lot of times they’ll say they’re seeing ASC codes but are unable to loop the network interface. If the NI is supposed to be loopable, and they’re seeing ASC from the NI… it’s entirely possible that there could be a physical trouble on the circuit.There are two main problems when telco reports this to you: a) they don’t usually have 56k circuits noted as to whether or not the NI should be loopable, and b) sometimes the NI will run on site power, and sometimes it won’t. You’ll need to dig into past tickets to find out what the usual symptoms are.
    • ATT: Not to be confused with the telco carrier AT&T, I’ve seen several people use this to refer to “at this time”.
    • ckt: Circuit.
    • CO: Central office.
    • CPE: Customer premise equipment. Usuallly, any equipment located at the customer site that the telephone company isn’t responsible for. This normally includes the CSU/DSU and the router; sometimes (like DSL circuits, for example), the telco may actually provide that equipment for the customer.
    • CWT/CCWT: Cleared while testing / came clear while testing. Basically, they saw a problem, but before they could narrow anything down, it went away.
    • DP/DPO: Dispatch / dispatch out.
    • ISW/IHW: Inside wiring / in-house wiring. Basically, this means any cabling that is past the telco demarc… the cabling that they are not responsible for.
    • HD: Helpdesk.
    • LCON: Local contact. When dispatching out to a site, the telephone company will usually ask for the name of the local contact, the phone number, and what the access hours are. Note that access means to wherever the telephone equipment is located, so sometimes even if the store is open, they may not have access (if it’s located in a locked managers office, for example).
    • MCOS/MOOS: MUX Code out of sync / MUX out of sync.
    • MOD: Manager on duty — another name for the store manager / acting supervisor at the customer site.
    • NTF: No trouble found.
    • tkt: Ticket.
    • TOK: Test ok.
    • VPE/P&E: Verify power and equipment.

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