dicnol的部落格

"Tiers" in the telecommunication global tends to have threefold definitions, depending on who you ask. What rank a bandwidth haulier is, is loosely definite at foremost and one and all has their own feelings of what level a toter could be. Here is my opinion:

Tier-1: [may be considered an RBOC or LEC - Regional Bell Operating Company or Local Exchange Carrier]

Tier-1 is a network in which solitary station unbound peers and consumers are repaired. The exchange cards function pays for none of it's theodolite.

Tier-1 is the best network support for milieu to deep businesses next to hypercritical reliability, stability, and measurability requirements.

Tier-1 can be an asset when it comes to manual labour DDoS attacks: if you ask/configure your Tier-1 supplier to null-route an IP they will implement the null-route at their borders, so there is no constituent of impregnation.

Examples of US Tier 1 carriers:

Qwest

AT&T (formerly SBC, Bell South, Southwestern Bell, Ameritech)

Savvis

Verizon (formerly MCI and UUNET)

Global Crossing

Level 3 (recently incorporate near Broadwing)

NTT Communications

Tier-2: [may be reasoned a CLEC (Competitive Local Exchange Carrier); has their own network, but too resells level 1]

Tier-2 is where the system mathematical function buys all or every of it's theodolite from a Tier-1 and resells it.

Tier-2 can be an authority if you have need of person to bequeath standard bandwidth, and especially if your entail is a one-member swear in position. If you buy from Tier-1 #1 in New York, and #1 has a difficulty near its Tier-1 #2 peering trained worker in New York, consequently all your assemblage from you to #2 may be bombastic. Your fitness to howl at #1 and get them to fix it will be limited, mega if the conundrum is near #2's bound skilled worker. A superb Tier-2 will display its upstreams and their peering points for trouble, and pilfer measures to assure that it doesn't feeling their clients. Even if you have need of multi-location installs, purchasing from a pious Tier-2 can be no-frills.

A Tier-2 that with the sole purpose responds to tough complications (e.g. whole indefinite quantity of an upstream intertwine) is no much helpful than a Tier-1 to cause who has multi-locations.

Pricing from Tier-2 ISPs is recurrently cheaper at the low-end (e.g. T1). Tier-2's will normally rout the tier-1's in evaluation "access services". But if you buy in the hundreds of megabits, a Tier-2 is likely to allude to by a long chalk complex than a Tier-1.

Tier-2's are unremarkably small companies, and are better able to "make deals", or sanction courtship of contracts, compose institution SLAs (Service Level Agreements), trench fibre to your entity in change for that autographed contract, etc. Unless you buy quaternate gigabits from your upstreams, if you deprivation to wad contracts near Tier-1s, you will belike end-up doing it through a middleman or different purchase chemical action.

Examples of US Tier-2 carriers:

XO Communications

Covad

Paetec/US LEC

Time Warner Telecom (recently incorporate next to Xpedius)

Eschelon Telecom Inc

Cogent Communications

Speakeasy

Embarq

McLeodUSA

AOL Transit Data Network

Covista

IDT Corp.

Tier 3: [wholesalers /resellers of level 1 and 2 networks]

Tier-3 are downstream patrons of Tier-2's. Tier-3 may supply you what looks like a solid terms.....but longterm reliability, performance, and measurability will probable suffer. For part of knowledge for your company a Tier-1 or Tier-2 are finer choices is almost both baggage. However, PowerNet Global is a big elision to this oversee due to their concrete substructure and contact near crucial players.

Examples of US Tier-3 carriers:

Trinsic

Excel

Primus Telecom

PowerNet Global

Access One Inc.

Splice Communications

Acceris

Whatever business organization postulation you stipulation met be assured to categorize what grade your on tap bandwidth providers are in your buying result. Ignoring this cause in your deliberations may event in less than optimal completing and contentment in the end. Make a formal conglomerate judgment.....leave relative quantity to break.