1 / 13

LAN Digital Audio

LAN Digital Audio. Greg Van Dyne December 4, 2007. Agenda. Introduction Technical Overview Protocols Demonstration Future Trends References. Introduction. Port Forwarding

bruce-wade
Télécharger la présentation

LAN Digital Audio

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. LAN Digital Audio Greg Van Dyne December 4, 2007

  2. Agenda • Introduction • Technical Overview • Protocols • Demonstration • Future Trends • References

  3. Introduction • Port Forwarding • Opening a port in a router or firewall residing in a private network in order to let a party from the outside world contact a user inside. For example, opening ports for VoIP and videoconferencing traffic makes two-way communications easier no matter which side initiates the call. Also called "port mapping," port forwarding can be done by manual configuration or by software. *definition courtesy of PCWorld.com

  4. Ports • What is a port? • represents an endpoint or "channel" for network communications • One computer sends data from port of one IP address to another • Port numbers can theoretically range from 0 to 65535 • Only one application can be used at a time on any given port • Why forward a port? • With routers, firewalls prevent direct comm. between IPs

  5. A Few Common Ports • 21 – FTP • 22 – Secure Shell (SSH) • 23 – Telnet • 80 – HTTP • 110 – POP3 mail • 3389 – Remote Desktop Protocol (RDP) • 6112 – Blizzard’s Battle.net gaming service (Unofficial) *Unofficial – not registered with IANA (Internet Assigned Numbers Authority)

  6. Some Familiar Concepts • TCP – Transfer Control Protocol - 2 computers directly connect, and remain connected for duration of session *similar to a telephone call • UDP – User Datagram Protocol – sends data and relies on devices in between to deliver properly. Not as reliable *like putting mail in mailbox • NAT – Network Address Translation – determines destinati0on of packets sent to network. This is where port forwarding comes into play.

  7. Static vs. Dynamic IP • Static • Usually ocnfigured within OS • Ensures that internal IP never changes • Ports can be forwarded once, and will not require any changes in the future • Dynamic • Internal IP fluctuates • Can cause port forwarding not to work • Port Triggering • Dynamic port forwarding

  8. Port triggering allows for port to to open only when a certain application is running • Once application stops, access to that port is turned off • Slightly more secure

  9. Things to consider The need to forward the packets that come to the router's forwarded port, and the need to rewrite them so that the private machine sees them as originating from the router Only one networked machine can use a specific forwarded port at one time Traditional port forwarding allows the entire world access to the port, thus security is reduced Ports can be changed within registry if unofficial

  10. Reverse Port Forwarding • Also called reverse tunneling • Composed of session server (SS) and session client (SC) • SS connects with session port, SC connects with session server component • SS tunes in to port that needs forwarded • When connection is done, it’s forwarded directly to SC with an accessible destination to that SC • Usually needed when a port is behind a router or firewall but that router or firewall is not configurable with normal port forwarding for one reason or another

  11. References • Cadden, C. (2006) “MP3 Player Market to Reach 286 Million Units by 2010.” In-Stat.com. Retrieved Nov. 23, 2007. http://www.instat.com/press.asp?ID=1648&sku=I N0603155ID. • Snell, J. (2004) “How AirTunes Works” Macworld.com. Retrieved Nov. 23, 2007. http://www.macworld.com/weblogs/editors/archi ves/000212.php. • Wikipedia. (2007) “Digital Living Network Alliance.” http://en.wikipedia.org/wiki/Digital_Living_Network _Alliance

More Related