However, since male connectors are more susceptible to injury than female, most expensive computing hardware these days has female connectors, while cables are male on both ends.
Since RS-232 defines signals that are not used for most standard communication, sometimes DB-25 connectors are missing unneeded pins.
For instance, with a terminal, it lets you use only 3 wires for a connection: transmitted data, received data, and signal ground.
However, in a modem connection, you really want to pay attention to DCD.
Most systems also allow you to use soft carrier where the system pretends that the DCD signal is always asserted.
Soft carrier is often a very good thing for certain devices.Originally, there was no standardization of the gender of connectors and serial devices.Both connectors and serial devices could be either gender.In fact, it's overkill for most standard communication.However, it's good enough to have become an industry standard.This is a pretty conservative figure and has been stretched as far as 1,000 feet.How far the limit can be stretched depends on the brand of terminal and computer you are using.Luckily, in standard types of communications only 9 of these pins are important: 1-8, and 20.DB-25 connectors are either male, with the pins sticking out, or female, with matching holes.This is something to keep in mind when connecting terminals to computers in other rooms.Because of the fact that RS-232 defines signals that go unused in standard types of communication, and because the traditional DB-25 connector is large an unwieldy (especially for small equipment, like laptops), many alternate serial connectors have come into widespread use.