When a service provider brings a coaxial line that delivers satellite or cable-based services, there is always a risk of damaging electric surges caused by lightning, static, or flash-over from other utility services. To minimize the risk, install surge protectors (aka surge suppressors).

Most satellite and cable-based services use RG6 coaxial cable with "F" type coax connectors. "RG" is a carryover from military ratings for coaxial cable performance and construction. RG6 coaxial cable has a center conductor with a "dielectric" material around it, a braided shield around the dielectric and finally an
outer plenum or PVC jacket to protect the cable from the elements.

Right where the service is delivered to your premises, a grounding block is installed. The ground block
provides feed-thru connections; the point where the coaxial service is connected to the cable that brings it into your premises (home, office, suite, etc).

The ground block also has a connection to the nearest available "code-compliant" electrical ground. For a home this may be a cold water spigget or pipe, for an office this may be the ground screw on an electrical outlet. I say "may be" because the US National Fire Protection Association publishes a set of codes (among many others) called the National Electric Code which further details how services should be grounded under varying circumstances; so for the sake of simplicity, let's assume the above examples for the home and the office are NEC compliant.

There are 2 prevalent technologies in use in the construction of coaxial surge suppressors: gas tube and solid-state. Both of these technologies conduct electricity once a device-rated voltage is reached across its terminals and effectively creates a low resistance (ideally zero resistance / short-circuit) path to ground; discharging the excess current harmlessly to ground and reducing the voltage spike to near zero volts.

The gas tube is a small device that has an amount of ionizable gas while the solid-state device uses semiconductor technolgy; both achieving similar protection. There are advantages and disadvantages to both which I won't get into because there are some other things to consider when deciding on a coaxial surge suppressor.

For satellite services, check with your service provider but the most popular and available satellite services
need a bandwidth just over 2Ghz (2000Mhz). The higher the bandwidth the better, but also more expensive.

For most cable or CATV based services, the bandwidth has been in excess of 1Ghz, but the new DOCSIS 2.0 cable service standard for new digital TV and higher speed cable modem services, will need bandwidth in the same range of the satellite service (in excess of 2Ghz). Not because the baseband or carrier frequencies will be changing but they will be squeezing more out of the "harmonic content" to achieve the higher bits per second.

Finally, there are coaxial inline surge suppressors (aka barrels) and ground block based surge suppressors.

The inline version is used when you already have a well grounded ground block delivery or if it comes with an extension (tail) of ground wire for you to hook up.

Note: using an inline surge protector without a grounded coaxial shield will not provide you with protection, because the discharge has no place to go but around the cable to where the surge came in and then find the nearest discharge path along the same cable.

The ground block based surge protector is a ground block and surge suppressor in one unit. They are rated for outdoor use in a metallic casing with provisions for running a ground wire which will ground your coax cable shield.

To summarize:
Check the specs, make sure the coaxial surge protector is rated for your service and performance; what technology type, surge voltage or clamp voltage ratings, indoor / outdoor use, grounding requirements and most importantly bandwidth (not enough bandwidth and you're killing your signal before it ever gets to your equipment.

Hope this helps