Renny的回答：TCP Port 4221 may use a defined protocol to communicate depending on the application. A protocol is a set of formalized rules that explains how data is communicated over a network. Think of it as the language spoken between computers to help them communicate more efficiently. Protocol HTTP for example defines the format for communication between internet browsers and web sites. Another example is the IMAP protocol that defines the communication between IMAP email servers and clients or finally, the SSL protocol which states the format to use for encrypted communications. TCP Port 4221 Here is what we know about protocol TCP Port 4221. If we do not have any information on port 4221 in our database, a counter will be set for TCP port 4221. After enough hits, we'll research this port and update the database. If you have information on TCP port 4221 that is not reflected in our database, please leave a comment or post your information on our Web Security Forum. We'll update our database so that the next user searching for port 4221 will have the most accurate information. PORT 4221 - Information Port Number: 4221 TCP / UDP: TCP Delivery: Yes Protocol / Name: vrml-multi-use Port Description: vrml-multi-use.'vrml multi user systems' Virus / Trojan: No Side note: TCP port 4221 uses the Transmission Control Protocol. TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered on port 4221 in the same order in which they were sent. Guaranteed communication over port 4221 is the key difference between TCP and UDP. UDP port 4221 would not have guaranteed communication in the same way as TCP. 英文资料查了点，举了HTTP和IMAP，可以初步理解了吧。 至于开启它，要有4221对应的服务，开启服务它就自动开启了，我不知道你的应用程序里哪里用到了它，我还没有开启它。貌似Windows是不能想开什么端口就开什么端口的，只能关闭和开启特定的一些端口。 希望对你有帮助，一起学习。 |
