User's Manual

Table Of Contents
IP Registration
AT+i Programmer‘s Manual Version 8.32 16-1
16 IP Registration
When iChip goes online in a dial-up environment, it is normally assigned a dynamic IP
address during PPP establishment. Since a different IP address is usually assigned every
session, it is not practical to use iChip as a server, since the clients do not know what IP
address to use. Furthermore, under these restrictions, there is no practical way to know
whether a specific system is online or offline. A similar problem occurs when using the
iChip LAN, which is configured to use a DHCP server. In this environment, a different IP
address is usually assigned every time the iChip LAN boots and connects to the LAN.
To overcome this problem, iChip incorporates built-in procedures designed to register its
IP address on a server system each time it goes online. Once registered, client systems
may interrogate the servers in order to verify the online status of a specific system and
retrieve its currently assigned IP address. The IP registration process is governed by
several AT+i parameters. Once these parameters are configured, iChip registers its IP
address accordingly when it goes online as a result of an explicit AT+i command
(
AT+iUP) or as a result of automated Internet session establishment procedures, such as a
triggered Internet session or when going online as a SerialNET mode server.
In cases where iChip uses a NAT gateway to the Internet, it can be configured to register
the NAT‘s IP address and a special port that is linked to iChip in the NAT‘s
configuration. See details in the RRRL parameter description. When this is the case, the
RRRL parameters (IP and port) are used instead of the local IP and port values that iChip
is assigned, in all registration methods (RRMA, RRSV, and RRWS).
iChip includes several IP registration methods, as described below.
16.1 E-Mail Registration
iChip registers itself by sending an e-mail that contains its ID information and current IP
address. When the RRMA parameter contains an e-mail address, iChip sends an e-mail
containing its current IP address or its RRRL to the address defined in RRMA during the
registration procedure. The syntax of the e-mail body is:
<BDY parameter contents>
iChip-<D/L/S> S/N:<RP5> Version:<RP1> HN:<HSTN> IP:<IPA or RRRL>
Port:<LPRT or 80 or 0> http:// <IPA or RRRL><CR><LF>
The subject line of the e-mail is:
"RING RESPONSE LINK From: iChip-<D/L/S> S/N:<RP5> Version:<F/W ver>
HN:<HSTN> IP:<IPA or RRRL> Port:<LPRT or 80 or 0>"
where,
Port is
LPRT if in SerialNET mode; 80 if not in SerialNET mode and AWS is enabled,
and 0 if not in SerialNET mode and AWS=0. The receiving end may refer to the contents
of the subject line to filter out this e-mail message.