假如要给 real / helix server配置防火墙(firewall)，对于其端口设置是必须了解的，除了大家熟知的554 rtsp端口，还有哪些呢，www.helixapp.com 专业流媒体服务网 为您讲解一下：

对于服务器而言，主要关心的是下面的端口:

554 TCP RTSP协议端口

1755  TCP MMS协议端口

7070  TCP PNA协议端口

80/1080/8080 TCP HTTP协议端口

34445-34459 UDP RTP/RDT的重发端口

假如需要作直播，还需要关注如下端口:

4040 TCP RealProducer 6.1使用的

5050 pre-G2 encoder 使用

500001-50050 TCPD/UDP Helix Producer 9 使用

80/1080/8080 Helix Producer 9 使用

另外，安装以后这些端口可能因为设定而有所变化

http://service.real.com/help/library/guides/helixuniversalserver/htmfiles/firewall.htm

Default Ports

The following section will help you to decide which ports to open on your firewall. If you do not want to open all the ports listed, refer to the detailed information at http://service.real.com/firewall.

Helix Universal Server Default Ports

The following tables list the default ports that Helix Universal Server uses to communicate with media clients and other server.

Helix Universal Server Ports for Communicating with Media Players

Activity	Port Number	Transport	Purpose
listen on	554	TCP	control channel for RTSP requests (data channel also, if TCP was requested)
listen on	7070	TCP	control channel for PNA requests (data channel also, if TCP was requested)
listen on	HTTP Port	TCP	HTTP requests, and RTSP, MMS and PNA cloaked through HTTP
listen on	1755	TCP, UDP	TCP control channel for MMS requests (data channel also, if TCP was requested); UDP resend requests by MMS
listen on	34445-34459	UDP	RDT/RTP client replies for UDP resends, etc.
send to	1024-5000	UDP	MMS media packet delivery
send to	1-65000	Multicast	MMS multicast media packet delivery
send to	6970-32000	UDP	data channel

Helix Universal Server Ports for Communication with Helix Administrator

Activity	Port Number	Transport	Purpose
listen on	Admin Port	TCP	connections to Helix Administrator
listen on	9090	TCP	Server Monitor traffic

Helix Universal Server Ports for Communication with Content Caching Subscribers

Activity	Port Number	Transport	Purpose
listen on	554	TCP	media distribution requests

Helix Universal Server Ports for Communication with License Subscribers

Activity	Port Number	Transport	Purpose
listen on	Admin Port	TCP	license subscriber initiation request
listen on	4321	TCP	license distribution accounting channel

Helix Universal Server Ports for Communication with Receivers

Activity	Port Number	Transport	Purpose
listen on	2030	TCP or UDP	data channel for pull splitting requests
send to	30001 -30020	TCP or UDP	live data distribution

Helix Universal Server Ports for Communication with Encoders

Activity	Port Number	Transport	Purpose
listen on	4040	TCP	control channel for RealProducer version 6 and 6.1 connections
listen on	6970-32000	UDP	data channel for RealProducer 6 and 6.1
listen on	4040	TCP	data channel for RealProducer 6.1 connections, if TCP was selected
listen on	5050	TCP	control channel for pre-G2 encoder connections
listen on	50001-50050	TCP or UDP	media packet reception from Helix Producer 9 in account-based transmitter mode
listen on	HTTP Port	TCP	negotiate transmitter settings for Helix Producer 9 in account-based transmitter mode
listen on	HTTP port	TCP	HTTP connection to Windows Media Encoder (Helix Universal Server pulls the stream)

Helix Universal Server Ports for Communication with Helix Universal Proxy

Activity	Port Number	Transport	Purpose
listen on	554	TCP	control channel for RTSP requests to Helix Universal Server
listen on	554	TCP or UDP	Helix Universal Proxy live requests
listen on	554	TCP	Helix Universal Proxy cache requests

Receiver Default Ports

In addition to the values shown in the follow table, a receiver will use all the values described in "Helix Universal Server Default Ports" if it is also serving its own content (separate from splitting).

Receiver Ports for Communication with Helix Universal Server

Activity	Port Number	Protocol	Purpose
listen on	554	TCP	RTSP requests from RealOne Player
send to	2030	TCP or UDP	pull splitting requests
listen on	30001 -30020	TCP or UDP	push splitting requests

Helix Universal Proxy Default Ports

The following tables list the default ports used by Helix Universal Proxy.

Helix Universal Proxy Ports for Communication with RealOne Player

Activity	Port Number	Protocol	Purpose
listen on	7070	TCP	PNA proxy requests
listen on	554	TCP	RTSP proxy requests
send to	6970-32000	UDP	data channel

Helix Universal Proxy Ports for Communication with Helix Universal Server

Activity	Port Number	Protocol	Purpose
send to	554	TCP	control channel for RTSP requests
send to	3030	TCP or UDP	data and control channel for pull splitting requests
send to	7070	TCP	control channel for PNA requests
send to	7802	TCP	cache requests to Helix Universal Server
send to	7878	TCP	cache requests to Helix Universal Server

Helix Universal Proxy Ports for Communication with Helix Administrator

Activity	Port Number	Protocol	Purpose
send to	9090	TCP	Server Monitor traffic
listen on	Admin Port	TCP	Helix Administrator

Encoder Default Ports

With Helix Producer 9, you can set up the encoder to function in different ways. The two Helix Producer methods of communicating documented in the following tables are legacy mode and account-based transmitter mode. When Helix Producer uses newer encoding methods, it imitates a transmitter. If you have set up Helix Producer to function this way, use the ports and protocols listed in "Helix Universal Server Default Ports".

Helix Producer 9 Ports for Account-Based Transmitter Mode

Activity	Port Number	Protocol	Purpose
listen on	80	HTTP	Helix Producer initiation requests in account-based mode
send to	50001-50050	TCP or UDP	media packet reception from Helix Producer in account-based mode

In RealProducer G2 (version 6) and later, you can instruct RealProducer to use TCP for the data connection. UDP is the preferred method, as it results in a better user experience, but TCP may be necessary if there is a firewall between the encoder and the Helix Universal Server. If you do opt to use TCP, port 4040 will be used for both the control channel and the data channel.

RealProducer Ports for Communication in Legacy Mode

Activity	Port Number	Protocol	Purpose
send to	4040	TCP	control channel
send to	6970-32000	UDP	data channel if UDP is selected for the Helix Universal Server connection (the actual port number is not configurable)
send to	4040	TCP	data channel if TCP is selected for the Helix Universal Server connection

Note: RealProducer 5 and earlier use a TCP data and control channel sent on port 5050.

Media Player Default Ports

The following table lists the communications ports used by RealOne Player, RealPlayer 6-8, Windows Media Player, and QuickTime Player. In addition to the settings listed below, RealOne Player inherits proxy settings (if they exist) from the default browser, although users can turn off this feature from the RealOne Player Preferences menu.

When Helix Universal Server receives a control channel request, it directs the data to the port number specified by the client. RealOne Player and RealPlayer choose UDP for the data channel, and indicate a data channel port number between 6970 and 32000. Windows Media Player also chooses UDP, and indicates a data channel port number between 1024-5000. If the client chooses TCP for the data channel, Helix Universal Server uses the same port number for both the control channel and the data channel.

Media Player Ports for Communication with Helix Universal Server or Helix Universal Proxy

Activity	Port Number	Protocol	Purpose
send to	554	TCP	control channel for RTSP requests (data channel also, if TCP was requested)
send to	7070	TCP	control channel for PNA requests (data channel also, if TCP was requested)
send to	HTTP Port	TCP	HTTP requests, and RTSP, MMS and PNA cloaked with HTTP
send to	1755	TCP, UDP	TCP control channel for MMS requests (data channel also, if TCP was requested); UDP resend requests by MMS
send to	34445-34459	UDP	RDT/RTP UDP resend requests
listen on	1024-5000	UDP	MMS media packet delivery
listen on	1-65000	Multicast	MMS multicast media packet delivery
listen on	6970-32000	UDP	data channel

Versions of RealPlayer earlier than RealPlayer G2, use the following ports.

RealPlayer versions 3 through 5 Communication Ports

Activity	Port Number	Protocol	Purpose
send to	7070	TCP	control channel for PNA requests; data channel, if TCP was requested
send to	80	TCP	control channel; data channel, if HTTP cloaking or HTTP streaming is used
listen on	6970 - 6999	UDP	data channel (not configurable)