This week, three Diversified Telecommunication Services stocks are improving their overall ratings on Portfolio Grader. Each of these stocks is rated an “A” (“strong buy”) or “B” overall (“buy”).

This week, 8×8 Inc. (NASDAQ:EGHT) is showing good progress as the company’s rating jumps from a B (“buy”) last week to an A (“strong buy”). 8×8 provides voice-over-Internet protocol creation platforms, hosted Internet PBX solutions, voice and video semiconductors, and related software. Shares of EGHT have increased 16.7% over the past month, better than the 4.8% increase the Nasdaq has seen over the same period of time. The stock has a trailing PE Ratio of 5.4. For more information, get Portfolio Grader’s complete analysis of EGHT stock.

Cogent Communications‘s (NASDAQ:CCOI) grade is moving up to a B (“buy”) this week from last week’s C (“hold”). Cogent Communications is a facilities-based provider of low-cost, high-speed Internet access and Internet Protocol (IP) communications services. Investors seem to agree with the upgraded status of the stock, and have pushed the stock up 8.2% over the past month. For more information, get Portfolio Grader’s complete analysis of CCOI stock.

This is a strong week for Atlantic Tele-Network (NASDAQ:ATNI). The company’s rating climbs to B from the previous week’s C. Atlantic Tele-Network is a provider of wireless and wireline telecommunications services in North America and the Caribbean. Wall Street has pushed the stock higher by 9% over the past month. For more information, get Portfolio Grader’s complete analysis of ATNI stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.