Access links to CE routers, or WAN links was delivered formerly via Leased lines which was very expensive. Further on circuit switching or packet switching methods was massively used in a variety of flavors, mainly FR, X.25, ATM, Ethernet and PPP.
ATM, is similar to packet switching, but uses fixed length cells (53Bytes - 48 bytes of data and 5 bytes of header information) instead of variable length packets. Data is divided into fixed-length cells and then transported across virtual circuits, which is best for simultaneous use of Voice and data, its main drawback is that overhead can be considerable, but one of its main advantages is that it supports high speeds (ATM provides data link layer services that run over SONET (Synchronous Optical Networking) Layer 1 links - Fiber links), where you can have up to OC-192 (STM64)rates.
On slow links (2 Mbit/s and below). ATM still makes sense, and this is why so many ADSL systems use ATM as an intermediate layer between the physical link layer and a Layer 2 protocol like PPP or Ethernet.
Please do check this link for more general details:
We are pleased to announce availability of Beta software for 16.6.3.
16.6.3 will be the second rebuild on the 16.6 release train targeted
towards Catalyst 9500/9400/9300/3850/3650 switching platforms. We are
looking for early feedback from customers befor...
Introduction Featured Speakers Luis Espejel is the Telecommunications
Manager of IENova, an Oil & Gas company. Currently he works with Cisco
IOS® and Cisco IOS XE platforms, and NX to some extent. He has also
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In this session you can learn more about Layer 3 multicast and the best
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