A Quick Overview of JNOS

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A Quick Overview of JNOS

• May 4, 2006

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Agenda

• Well, not so much JNOS as IP/Packet
• Technical Details
• Capabilities
• Infrastructure

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Protocols

• Normal packet uses the AX.25 protocol
• This is a link level protocol, which has no
  inherent routing capability
• AX.25 does a good job of assuring delivery of the
  data
• AX.25 was specifically designed for radio circuits

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Internet Protocols

• The Internet protocols are actually a stack of
  protocols (of which AX.25 is one)
• The basic IP protocol, simply allows a message
  to pass from one network to another
• The Transport Control Protocol (TCP) allows a
  session to be established between two nodes
• Most commonly, TCP is layered on top of IP, thus
  TCP/IP

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Other common protocols

• TCP is one of hundreds of protocols that can be
  layered on IP
• Other common protocols
• UDP
• ICMP
• ipencap
• SMP
• Each of these has its own coordination rules

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Still More Protocols

• There is yet another layer of protocols which can
  overlay the above list. Usually, they use TCP
• Some common/useful ones
• http
• pop3
• smtp
• ftp
• telnet
• This multiple layer arrangement of protocols is
  what makes the Internet work

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IP - Packet

• To marry networks of different types, the
  encapsulation protocols were developed (IPENCAP,
  IPIP, etc.)
• For our purposes, there are two types of
  encapsulation that are interesting
• Encapsulating IP packets in AX.25 for
  transmission over radio
• Encapsulating AX.25 packets in IP for
  transmission over the Internet

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What can we do with it

• The basic idea is to graft the wired Internet and
  radio packet networks
• In principle, then, a packet could be routed
  across the Internet, to reappear on the packet
  network somewhere else
• Internet packets can be sent out over radio, and
  then piped back into the Internet (or more
  interestingly, a local LAN that uses Internet
  protocols)

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IP / Packet integration
The Internet
Packet Station
Packet Station
A packet station with one foot in the Internet is
called a Gateway
Packet Station
Packet Station
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IP / Packet Integration
Packet Station
Packet Station
LAN
LAN
PC
PC
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IP / Packet integration
The Internet
Packet Station
Packet Station
Packet Station
LAN
Packet Station
LAN
PC
PC
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The IP Magic

• The network is broken into subnets
• There is a special gateway called a HamGate
  responsible for each subnet
• Every HamGate knows which subnets every other
  Hamgate has responsibility for
• The HamGates know both the RF and wired Internet
  address for every HamGate
• Midland county has four subnets

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The IP Magic

• What IP brings to the table, more than anything
  else, is routing
• KB8QWQ puts an IP packet in the air addressed to,
  say, KA8NCR
• A HamGate (currently wb8rcr.ampr.org) sees the
  packet and recognizes
• The address is not the Midland subnet
• dtwgate.ampr.org is responsible for KA8NCRs
  subnet
• The HamGate knows how to get to the HamGate that
  is local to the recipient
• wb8rcr.ampr.org sends the packet along to
  dtwgate.ampr.org
• dtwgate.ampr.org knows which RF port to use to
  get to KA8NCR and sends the packet out over the
  radio

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JNOS

• JNOS is a packet program that contains several
  features
• It can be a full-service BBS
• It can transfer packets from one network to
  another
• Radio-Radio (e.g. different frequencies)
• Radio-Internet
• Internet-Radio
• It can encapsulate packets transferring from one
  network to another
• It includes a number of basic Internet-style
  servers

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JNOS Servers

• JNOS may include some servers
• SMTP
• POP3
• FTP
• Telnet
• WWW
• It also can include some packet-style services
• Packet BBS (full-service, and then some)
• Memory of VIAs
• Conference server
• Packet-style services available over AX.25 or
  Telnet

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Example Applications

• Send packet messages using PC email clients
• Transfer files using PC FTP clients
• Multi-station chat mode using conference server,
  IP and AX nodes
• eMail addressed to gateway can be automatically
  forwarded to IP or packet BBS (e.g. current
  W8KEA)
• Telnet over WiFi from hostspot to gateway, and
  thence on to packet

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Example Applications

• Since JNOS acts as both a server and packet
  station, a PC on the LAN does not require special
  packet software to use the radio
• Differences between brands of TNCs are masked by
  JNOS and/or use of familiar PC client software
• Responders on, for example, the LECs LAN could
  use normal email to contact the state EOC, even
  if the LECs Internet were out of service

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Proposed Infrastructure
The Internet
Bay City
Points West
Hospital Gateway
Jerome Gateway
Harrisville Via Tawas
Packet Station
LAN
LEC or other county facilities
PC
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Gateway Thoughts

• The gateways can support up to about 100
  interfaces
• Long-haul links should be point-to-point,
  preferably on different frequencies than local
  access frequencies
• May want to consider some UHF/Microwave links for
  higher speed in key applications
• LEC Hospital
• Hospital Bay City
• Either gateway to new, nearby gateways