mobile Internet

cellular handsets:
PHY: All digital
Signaling:
SMS, Short Message Service, up to 160 bytes
SMS, EMS use control channels while MMS use regular channels shared by data and voice.

Media Access: TDMA for multiplexing, using one of 8 time slots repeatedly

GSM, Circuit Switching, 9.6 (*2), 12.4(*2, HSCSD)
GPRS, General Packet Radio Services, Packet Switching, 9.05 kbps/13.4 kbps (*1,2,3,4)
WAP, content bearer protocol, certificate, cookies
WML, wireless markup language (or HTML-C as in i-Mode, XHTML)
MMS, Multimedia Messaging Service

Tariff
GPRS vs. GSM
pricing based on data volume or air time

Business Issues:
Will MMS make a hit?-
Function Integration
1. Fundamental questions: Do people like Swiss Army Knife? Video phone,
Recorder-TV,
British Royal Navy Sea Harrier (http://www.targetlock.org.uk/seaharrier/)
Format convergence products
2. DVD-Combo, DVD/VCD/CD
3. Card Reader, SD/SMC/MMC/CF

Advanced Applications
Positioning, LBS, GPS required for high precision

Security features
WIM: A Wireless Identity Module (WIM) can contain
both trusted and client certificates, private keys
and algorithms needed for WTLS handshaking,
encryption/decryption and signature generation.
The WIM module can be placed on a SIM card
and is then referred to as a SWIM card.

Social Issues:
base stations in communities
Near Fields

3G Technology Trends
Spread Spectrum: CDMA vs. TDMA (so called 3G)

MMS business issues
1. archiecture of MMS delivery systems
2. comparison to Internet

Principles of SS
1. from FDMA, TDMA to CDMA
2. related applications: IS-95, W-CDMA, 802.11

authentication and billing of wlan with SIM card

1. authentication
2. billing
3. coverage of both 802.11 & GPRS/3G
4. roaming across APs and WISPs
5. user base