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User’s Manual
ESERV-10 device server works in three different operating modes, each of which put emphasis on
a particular functionality. First, ESERV-10 is able to operate as a serial device server in both server
and client modes. Second, ESERV-10 functions through sending and receiving e-mail by using
SMTP (Simple Mail Transfer Protocol) and POP3 (Post Office Protocol) protocols, either
automatically or manually. Third, the remote control of ESERV-10 can be easily performed over the
network or locally with AT commands like in modems.
ESERV-10 device server includes the core protocols of TCP/IP and a built-in Web server. The
Internet Protocol (IP) is used for network communications and the Transmission Control Protocol
(TCP) to assure that no data is lost or duplicated, and that everything sent to the connection arrives
correctly at the target. The built-in Web server uses a graphic Java applet, which downloads from
the device server to the browser. This applet works as a virtual user interface for the device.
ESERV-10 device server can handle all Internet related functions by acting as a modem towards
the device connected to a serial port.
Internal Software
ESERV-10’s internal software consists of a TCP/IP stack, an embedded HTTP/Web server and
application software for a serial device connectivity.
OSI Layer
ESERV-10 Implementation
7 – Application
HTTP 1.1 Serial port POP3 SMTP BOOTP TFTP Serial
port Control
6 – Presentation
5 – Session
4 – Transport
TCP
UDP
3 – Network
IP version 4, ICMP, ARP
2 – Link
IEEE 802.3
1 – Physical
10Base-T Ethernet (Twisted pair)
Viola Systems’ Ethernet driver, TCP/IP stack, HTTP/Web server and operating system are
optimized for embedded devices and are implemented with ANSI-C to ensure portability.
ESERV-10
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Viola Systems Ltd.