It uses packets of 1,024 bytes and requires an 8-bit clean connection. The main difference is that e is a streaming protocol and is thus suited only to reliable network connections. It is a streaming protocol and expects a 7-bit data path. 8-bit characters are quoted, which can make it very inefficient. This is the System V Release 4 version of the g protocol.
All protocols allow for some variation in packet sizes, timeouts, etc.
Usually, the defaults work well under standard circumstances, but may not be optimal for your situation. The g protocol, for instance, uses window sizes from 1 to 7, and packet sizes in powers of 2 ranging from 64 through 4096. If your telephone line is usually so noisy that it drops more than 5 percent of all packets, you should probably lower the packet size and shrink the window. On the other hand, on very good telephone lines the protocol overhead of sending acknowledgments for every 128 bytes may prove wasteful, so you might increase the packet size to 512 or even 1,024. Most binaries included in Linux distributions default to a window size of 7 and 128-byte packets.