Showing posts with label cells. Show all posts
Showing posts with label cells. Show all posts

Tuesday, December 3, 2013

mobile operators draw a new small cell order in 2014

Mobile operators are frequently described to be under pressure to upgrade the capacity of their networks in response to unrelenting demand for mobile data services.  Small cells are one such technology deemed indispensible for operators. As a case in point, AT&T announced that it will aggressively push to deploy 40,000 small cells by the end of 2015 under its Project Velocity IP (VIP). In the meantime, Verizon Wireless expressed the desire to deploy small cells but only if they are inexpensive.
What the two leading North American operators are saying is that inexpensive small cells, specifically outdoor carrier deployed compact base stations, makes possible for high-volume deployments. However, small cells remain to date an object of great debate with operators actively engaged in field trials during 2013 while promises of deployments are deferred into the future. This begs the question: how do we map the current state into the deployment cycle of a new technology? What do operators see as the challenges holding up small cell deployments? What are their key requirements for small cell deployments? What type of small cells will be deployed and how do the different backhaul solutions stack up

source: fiercewireless.com

Tuesday, November 19, 2013

Asynchronous transfer mode in UMTS

It is a telecommunications concept defined by ANSI and ITU standards for carriage of a complete range of user traffic including voice , data and video signals.
ATM was developed to meet the needs of the Broadband Integrated Services Digital Network, as defined in the late 1980 s, and designed to unify telecommunication and computer networks. It was designed for a network that must handle both traditional high-throughput data traffic (e.g., file transfers), and real-time, low-latency content such as voice and video. The reference model for ATM approximately maps to the three lowest layers of the ISO-OSI reference model: network layer, data link layer and physical layer.  ATM is a core protocol used over the SONET/SDH backbone of the public switched telephone network (PSTN) and Integrated Services Digital Network (ISDN), but its use is declining in favour of all IP.

ATM provides functionality that is similar to both circuit switching and packet switching networks: ATM uses asynchronous time-division multiplexing,  and encodes data into small, fixed-sized packets (ISO-OSI frames) called cells. This differs from approaches such as the Internet Protocol or Ethernet that use variable sized packets and frames. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins. These virtual circuits may be “permanent”, i.e. dedicated connections that are usually pre configured by the service provider, or “switched”, i.e. set up on a per-call basis using signalling and disconnected when the call is terminated.