Note that if you plan to connect your workstation's ethernet port directly to the port on the Ascend unit, without a hub in between, you need to use a "crossover" cable: a 4-pair RJ-45 cable with pins #2 and #3 swapped. (Ascend now provides a crossover cable in the box of every Pipeline 50/50-HX.) You'll also need a 10baseT ethernet card.
NOTE: Make sure you don't mistakenly use a crossed RJ-45 cable to connect the WAN port of your Ascend to your telco ISDN jack! This may have harmful results!