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IEEE Globecom 2010: Mobile Communication and IPv6
- 2. 2 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 3. So what, you might ask
• We will have 4+ billion cellular phones
• A growing number are IP capable
• Trend toward Always-On applications
• Push Email, VoIP, IM, multimedia services
• Currently, many operators need to run both a circuit
switched and an IP network. This leads to higher CAPEX
and OPEX.
• LTE is happening now, will be soon doing voice over IP only
• In the future, services will migrate to IP.
• So the choice is between
• IPv4 with NAT frequent Keep-Alives
• IPv6 and long lived connections
3 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 4. NATs with keep alive messages
• IPv4 Mobile Devices are usually behind IPv4 NATs
• Always on application are becoming more prevalent
• Push Email, VoIP, IM, etc.
• Applications that want to be reachable need to send periodic
Keep-Alives to keep NAT state active
• Current NATs require Keep-Alive from 40 seconds to 5 minutes
• Need to implement for minimum ( ~30 seconds)
• Sending of NAT periodic keep-alive messages decreases mobile device
standby time by several days
• Not a problem for devices with power cords, but for mobile devices it is a
big problem
There should be NO The UDP inactivity timer in NATs causes the public
Client, Private
IPv4 address 1
NATs between the UDP port 6538 to be assigned to a different mobile, if
terminal and the server! the mobile does not send any data within a certain
amount of time, about every 40 seconds …
Client, Private
IPv4 address 2 UDP port = 6538 Server, Public IPv4 address 3
4 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 5. Not All NATs are
created equal
• UDP and TCP timeouts vary widely
• Several different NAT traversal mechanisms are needed
• STUN, TURN, ICE, Teredo
• All bring additional terminal and network complexity
• Additional CAPEX and OPEX
• All NAT traversal mechanism do open some security holes.
• Even worse, you might be behind different NATs at different times of the day
• Home, office, hotspot networks often use different types of NATs.
• Each requiring a different traversal mechanism
• Performance over 3G is even worse
• UMTS radio state management prevents the mobile device from entering
sleep mode, often reducing standby time by days.
• http://www.niksula.hut.fi/~peronen/publications/haverinen_siren_eronen_vt
c2007.pdf
5 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 6. T-Mobile USA IPv6 Trial
• IPv6 trial in T-Mobile USA with Symbian
phones
• Nokia N900 is also supported, using a beta
DualStack implementation
• T-Mobile USA is using DNS64/NAT64 to
get IPv4 connectivity
6 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 7. What else is going on?
• Nokia N900 running Linux
• Add-on support for IPv6 Dual Stack
• http://n900-ipv6.garage.maemo.org/
• https://code.google.com/p/n900ipv6/wiki/README
• http://code.google.com/p/n900ipv6/wiki/LDPreloadNat64
7 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 8. Problems we are finding
• Lack of support for IPv6 in applications
• Applications that are not using standard socket calls or other
‘tricks’
• Servers that are IPv4 only
• Use of IPv4 literal addresses
• NAT problems
• multilevel NATs
• poor quality code in some NATs.
8 © 2010 Nokia Mobile Communication and IPv6 John Loughney
- 9. Take-away thoughts
• I want my device to help me to
communication, but I cannot
communicate with an IP address or if
my battery is dead.
• IPv6 is the only scalable technology to
enable multiple services,
interconnecting with other networks.
• IPv6 is now.
9 © 2010 Nokia Mobile Communication and IPv6 John Loughney