The Civilian Defense Front is a faction founded by civilian survivors of The Flash with the intent of protecting other wastelanders, leading them to a better life and to a new nation built out of the ashes. Until 2096, in which the CDF was converted into the military of the newly founded People's Republic of Tidewater (PRT), and due to it's funding from Brazil, the PRT improved its standards of training and was able to supply themselves with better equipment. By the events of ATF: Deep Six, the PRT are strong enough to rival the USCPF.
CDF as a Militia
The CDF pre Deep 6 are much less organized, however they still recieve basic training. As a militia, they will use whatever weapons they can find, and scavenge for (which is primarily the Ithaca). The CDF still have roles, some with different names then their military counterparts. They also often work with the USCPF, and they try to reach similar goals. The CDF do not have any ranks as a militia.
CDF in Deep Winter
The CDF have a very special presence in Deep Winter. They mainly protect the Den, but the CDF does hire people to go to the surface to scavenge. The Den does not allow any mutants in (above RAD 3, something that even though nobody knows the scientific name for ((IC'ly at this time)) can still be seen from the way a mutant acts). The CDF will work with SEAL's, who sometimes deliver supplies and help out.
You should also note that the CDF are in their very early days, meaning they don't even refer to themselves as the CDF, but usually as militia men or something.
CDF as a Military
The CDF are MUCH different as a military. The rules are stricter, the style of roleplay is much more formal, and there are ranks (Private to Sergeant for regular roles, Platoon Sergeant to Lieutenant for Squad Leader, and a variety of other IC ranks for Field Officers+). They frequently work with the MEB and TIFEPOL, and are stationed in Fort Wilmington.
The CDF weapons guide can be found above here.
With the CDF being both a militia and a military, the CDF is structured so people can RP fluidly between games. The CDF recently underwent a change from ranks to roles, and as mentioned earlier, pre-military CDF do not have (IC) ranks,. However, they have roles, which is also something the military has as well, with some different names. The current leader of the CDF is Seamoous.
There are 12 non-leadership roles in the CDF. Each are designed to serve their own purpose, both in the militia, and in the military.
Repair vehicles around settlements or Fort Wilmington.
Repair other forms of machinery around settlements or Fort Wilmington, but also in combat situations.
Operate radios to help keep everyone in contact.
Get whatever information possible, serve as a way to communicate without technology.
Standard fighting force.
Pick off enemies from a distance and serve as a watchman.
Treat the wounded, both on the battlefield and at settlements/Fort Wilmington.
Run shops, maintain guns.
Operate heavy weaponry.
Hostilities with the USCPF
As of ATF: Deep 6, the tensions between the eastern CDF and USCPF have erupted into full blow war. As for the west (and Hawaii), the CDF and USCPF maintain an uneasy peace, diplomatic relations still ongoing, but both factions having full support for their side of the war in the east.
Hostilities with the REDS
The REDS are a bandit faction of remnant pro-US CDF, forced out by the MEB. They sympathize with the United States, and see the PRT as an evil force. They will often carry out attacks on CDF, and in general, can cause severe problems.