"Tiers" in the Telecom world has a tendency to have multiple definitions, depending on who you ask. What red bandwidth carriers, loosely defined at best, and everyone has an opinion about what enters the carrier can be. Here is my opinion:
Tier-1 [can be considered a RBOC or lectures - the regional telephone company or local exchange carrier]
Tier-1 is a network where the only village without peers and customers are servisirati.Mrežnom operator pays for none of this transit.
Tier-1 backbone network is optimal for medium and large businesses with mission critical reliability, stability and scalability requirements.
Tier-1 may be an advantage when it comes to handling DDoS attacks: If you / configure Tier-1 service to NULL-time IP they will spend a null-route to their limits, so it's no saturation point.
Examples of Tier 1 U.S. carriers:
Qwest
AT & T (formerly SBC, Bell South, Southwestern Bell, Ameritech)
SAVVIS
Verizon (formerly MCI and UUNet)
Global Crossing
Level 3 (recently merged with Broadwing)
NTT Communications
Tier-2 [can be considered a CLEC (competitive local exchange carrier), has its own network, but also resells tier 1]
Tier-2 is where the network operator to buy all or some of the transit from the Tier-1 and resells.
Tier-2 may be an advantage if you need someone to provide quality bandwidth, especially if your need is to install one place. If you buy from Tier-1 # 1 in New York and # 1 has a problem with their Tier-1 # 2 looking at the router in New York, and then all of its traffic from you to # 2 May be affected. Your ability to yell at # 1 and get them to fix it will be limited, especially if the problem with # 2 boundaries usmjerivač.Dobar Tier-2 will monitor the upstreams and seeing points of trouble, and take measures to ensure that no impact on their customers. Even if you need more space to install, buy from a good Tier-2 may be useful.
Tier-2 to only respond to serious problems (eg, total failure upstream link) is more useful than the Tier-1 to someone who has more space.
Prices from Tier-2 ISP is often cheaper in the low-end (eg T1). Tier-2 is often going to win the Tier-1 in the price of "access to services." But if you buy in the hundreds of megabytes, Tier-2 is likely to quote much more than a Tier-1.
Tier-2's are usually smaller companies, and are better able to "engaged" or admit to connect the contract to write a custom SLA (Service Level Agreement), the trench fiber to your site in exchange for which they are signed contract, etc. in addition if you buy more gigabytes of upstreams, if you want to group contracts with Tier-1, you will probably eventually be done through a wholesaler or other purchasing mechanism.
Examples of the U.S. Tier-2 carriers:
XO Communications
Covad
Paetec / US lectures
Time Warner Telecom (recently merged with Xpedius)
Eschelon Telecom Inc.
persuasive communication
Speakeasy
Embarq </ P>
McLeodUSA
AOL Transit Data Network
Covista
IDT Corp.
Level 3: [wholesale / retailers Tier 1:02 networks]
Tier-3 are downstream customers are Tier-2-A. Tier-3 can give you what looks like a good price ..... but long-term reliability, performance, scalability, and will likely suffer. For piece of mind for your business to Tier 1 or Tier-2 are the better choice is almost every case. However, powernet Global is a big exception to this rule because of its solid infrastructure and relationships with big players.
Examples of the U.S. Tier-3 brackets:
intrinsic
Excel
Primus Telecom
powernet Global
Access One Inc
Splice Communications
Acceris
Regardless of the business application must be met to be sure to consider what your order available bandwidth services in your purchasing decision. Ignoring this factor in discussions May result in less than optimal implementation and satisfaction in the end. Make a smart business decision ..... leave anything to chance.