The fixed line telecommunications sector was the top performing category in London on Wednesday with gains from heavyweight firm BT Group providing a boost.BT was trading at an all-time high of 360.3p by 15:15 today, up 1.66% on the day, after Goldman Sachs upgraded its rating on the stock to 'conviction buy'.The US bank also sees more upside to current prices in spite of the already-impressive 56% jump in the stock so far this year; it raised its target from 400p to 490p.KCOM, Telecom Plus and Daisy Group were also making decent gains today in the fixed telecom sector.Cable & Wireless Communications, the telecoms firm focused in the Caribbean and Central America, was up 1.78% at 41.72p in afternoon trade, its highest level since July.The company revealed on Monday that subsidiary Monaco Telecom is selling its Algerian satellite communication business Divona for $1.4m on a cash-free and debt-free basis, with proceeds being used for general working capital purposes.Goldman raised its target price for the stock on Wednesday from 45p to 50p.Top performing sectors so far todayFixed Line Telecommunications 4,105.48 +1.40%Tobacco 35,801.97 +0.47%Life Insurance 6,502.94 +0.45%Oil & Gas Producers 7,767.25 +0.42%Construction & Materials 4,330.28 +0.27%Bottom performing sectors so far todayHousehold Goods & Home Construction 10,155.60 -1.22%Personal Goods 23,298.50 -1.19%Electricity 9,135.97 -1.12%Aerospace and Defence 4,987.61 -1.11%Chemicals 9,875.61 -0.95%BC