Nortel Networks Ltd. is trading at an enterprise-to-sales multiple that's closing in on a four-year low, prompting RBC to cut its price target to $18 (U.S.) from $22. "Nortel still lacks a competitive product offering in numerous segments and also lacks the broad scale to compete at a global level," writes analyst Mark Sue. And while Nortel is making large bets in new growth segments like WiMax, next-generation wireless-network gear known as 4G and provider backbone transport (PBT), he figures these lines may not impact the profit and loss statement for some time. "So, investors taking a look at the stock at current levels must have a multi-year horizon," he suggests. The stock has slipped 2 cents to $16.42 on the NYSE Thursday morning.