Legacy Support: Asynchronous serial data (non-IP) over UDP

Supposed you want to send async data over the IP network to another end which is also running async serial data (non-IP). A viable solution is to use udptn, which is to transport asynchronous serial data over udp.


Declare your serial interface as async

interface se0/2

physical-layer async

load-interval 30

keepalive 10



Configuring the line terminal (Enabling udptn automatically)

line 3 (depends on which line terminal is associated to your async hardware)

dispatch-timeout 1000 (in milliseconds, this means data will be sent over every 1s)

dispatch-character 13 (means data will be sent over every new line)

no session-timeout

modem inOut (bi-directional communication)

transport output udptn (async data will be sent out using udp)

autocommand udptn (remote ip address to be sent to)



The udptn command can only be executed in privilege exec mode, so if you want to enabling it manually:

Router# udptn </transmit or /receive>

You can verify using your hyperterminal, whatever you type will be displayed over the other end of the hyperterminal.



3 thoughts on “Legacy Support: Asynchronous serial data (non-IP) over UDP

  1. Good day I was luck to seek your subject in yahoo
    your topic is outstanding
    I learn much in your subject really thanks very much
    btw the theme of you website is really exceptional
    where can find it

  2. Thanks for the configuration.
    I’m trying to build this in my lab, but i’m not getting a connection between the two host.
    Wich cable are used for the connection: host to router?
    Thanks for the advise

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s