What TCP port to use with SeaCat
SeaCat requires to specify one TCP port that is eventually used for client-gateway communication. Clients connect to this port to establish TLS channel that is used to exchange requests and related responses. SPDY-based communication protocol is used for traffic in this channel.
SeaCat: Protocol stack
TCP ports reachability
Google performed investigation during WebSocket implementation (late 2009) that showed surprising facts about success rate of client-to-server connections:
- HTTP port 80: 67%
- Custom TCP port (61985): 86%
- HTTPS port 443: 95%
The reason for low HTTP score is that the Internet is today full of proxies and firewalls that are configured to be transparent to HTTP traffic. However, non-HTTP traffic doesn't successfully pass them. Detailed reasoning can be found here: SPDY Essentials presentation from Google at approx. 18th minute of the video.
443 or custom port
SeaCat communication protocol is up to Session layer compatible with HTTPS protocol stack, HTTPS client that connects to SeaCat gateway is politely rejected with no harm on both sides. SeaCat traffic is indistinguishable from HTTPS traffic for intermediates on the network path, and,therefore, it shares the same success rate of connections. For these reasons TCP port 443 is recommended choice for SeaCat.
If for whatever reason you cannot use this port, use any TCP port above 1024 (non-reserved ports). You will likely got little bit worst connection success rate but still useful for practical deployments in common network scenarios.
Do you want to review your SeaCat-related design proposal?
Do you have a question we didn’t cover?
Do you want to give some feedback?
Feel free to contact us firstname.lastname@example.org.
You Might Be Interested in Reading These Articles
At our company, we develop our own software products that we offer to our clients and often also run ourselves. So far our company has operated its IT infrastructure — about 30 virtual servers—on a public cloud, specifically on MS Azure.
Published on July 01, 2018
Containerization is an alternative for full machine virtualization. You probably know well-known containerization technology from Docker or Rocket. However, this article addresses the pros and cons of mobile “containerization” or wrapper used to isolate the mobile app from the mobile operating system or other applications installed on the same device. These type of “containerization” work in a different way.
Published on September 27, 2016
Let us share with you fresh news from the SeaCat kitchen. A few weeks ago we had a workshop with one potential customer who was currently working on a mobile application which should access Oracle Business Intelligence (BI) suite, basically Oracle Business Intelligence Mobile HD based solution. We piloted Oracle BI SDK & SeaCat integration.
Published on November 30, 2014