* Ceasefire deal reached between Ukraine, Russia
* Cisco shares rally after results; Tesla falls
* TripAdvisor soars on results; Expedia to buy Orbitz
* Indexes up: Dow 0.5 pct, S&P 0.8 pct, Nasdaq 0.9 pct (Updates to close)
By Ryan Vlastelica
NEW YORK, Feb 12 (Reuters) - U.S. stocks ended sharply higher on Thursday, with a rally in technology stocks leading the Nasdaq to a 15-year high, while a ceasefire agreement between Russia and Ukraine also eased tensions.
The day's gains were broad, with eight of the 10 primary S&P 500 sectors rising, and the S&P information technology sector rose 1.6 percent in its third straight daily advance. Cisco Systems climbed 9.4 percent to $29.46 in the network equipment maker's biggest one-day jump since May 2013 after earnings and revenue beat expectations.
TripAdvisor Inc soared 22.5 percent to $82.40 a day after revenue topped forecasts. Fellow online travel company Expedia jumped 14.5 percent to $89.57. Earlier, Expedia agreed to buy Orbitz Worldwide for about $1.33 billion.
With 76 percent of the S&P 500 having reported, about 71.4 percent of companies have topped earnings expectations, according to Thomson Reuters data, while 56.8 percent have topped on revenue. That compares to the long-term average of 63 percent for earnings and 61 percent for revenue.
Overseas, leaders of Germany, France, Russia and Ukraine agreed a deal to end fighting in eastern Ukraine, potentially removing a concern for global investors, although the pact remained fragile. The news contributed to oil prices advancing 4.9 percent, which in turn lifted the S&P energy index 1.3 percent.
"There's definitely a feel-good situation leading from the reduction in geopolitical risk, while the rise we're seeing in the energy sector is really helping the overall benchmark," said Michael Mullaney, chief investment officer at Fiduciary Trust Co in Boston.
U.S. economic data was tepid, as initial jobless claims rose more than expected in the latest week, while retail sales barely rebounded in January. In addition, business inventories rose less than expected in December.
The Dow Jones industrial average rose 110.24 points, or 0.62 percent, to 17,972.38, the S&P 500 gained 19.95 points, or 0.96 percent, to 2,088.48, and the Nasdaq Composite added 56.43 points, or 1.18 percent, to 4,857.61.
The Nasdaq ended at its peak of the session, the highest level for the index since March 2000, while the S&P 500 ended about 0.1 percent below closing record, set on Dec. 29.
Tesla Motors dropped 4.7 percent to $202.88 after it missed fourth-quarter sales targets and analysts' profit expectations.
American Express shares dropped 6.4 percent to $80.48 as the biggest drag on the Dow after it said Costco Wholesale would stop accepting its cards in the United States from next April, after a renewal agreement could not be reached.
NYSE advancers outnumbered decliners 2,403 to 685, for a 3.51-to-1 ratio; on the Nasdaq, 1,931 issues rose and 806 fell, a 2.40-to-1 ratio.
The S&P 500 posted 69 new 52-week highs and no new lows; the Nasdaq Composite recorded 123 new highs and 20 new lows.
About 6.72 billion shares traded on all U.S. platforms, according to BATS exchange data, below the month-to-date average of 7.31 billion. (Editing by Bernadette Baum and Nick Zieminski)