<!-- $Id$ -->

<!-- Entities often used in the documentation -->

<!ENTITY fhg "FhG FOKUS">
<!ENTITY iptel "<ulink url='http://iptel.org'>iptel.org</ulink>">
<!ENTITY ser "SER">
<!ENTITY sername "SIP Express Router">

<!ENTITY serhome "http://iptel.org/ser">
<!ENTITY serbugs "http://iptel.org/ser/bugs">
<!ENTITY serhelp "http://mail.iptel.org/mailman/listinfo/serhelp">
<!ENTITY serusers "http://mail.iptel.org/mailman/listinfo/serusers">
<!ENTITY serdev "http://mail.iptel.org/mailman/listinfo/serdev">

<!ENTITY serhomelink "<ulink url='&serhome;'>&serhome</ulink>">
<!ENTITY serbugslink "<ulink url='&serbugs;'>&serbugs</ulink>">
<!ENTITY serhelplink "<ulink url='&serhelp;'>&serhelp</ulink>">
<!ENTITY seruserslink "<ulink url='&serusers;'>&serusers</ulink>">
<!ENTITY serdevlink "<ulink url='&serdev;'>&serdev</ulink>">

<!ENTITY serhelpmail "<email>serhelp@iptel.org</email>">
<!ENTITY serusersmail "<email>serusers@iptel.org</email>">
<!ENTITY serdevmail "<email>serdev@iptel.org</email>">

<!-- Often used acronyms -->

<!ENTITY sip "<acronym>SIP</acronym>">
<!ENTITY sdp "<acronym>SDP</acronym>">
<!ENTITY rtp "<acronym>RTP</acronym>">
<!ENTITY pstn "<acronym>PSTN</acronym>">
<!ENTITY http "<acronym>HTTP</acronym>">
<!ENTITY uri "<acronym>URI</acronym>">
<!ENTITY url "<acronym>URL</acronym>">
<!ENTITY uac "<acronym>UAC</acronym>">
<!ENTITY uas "<acronym>UAS</acronym>">
<!ENTITY ua "<acronym>UA</acronym>">
<!ENTITY nat "<acronym>NAT</acronym>">
<!ENTITY ip "<acronym>IP</acronym>">
<!ENTITY udp "<acronym>UDP</acronym>">
<!ENTITY ietf "<ulink url='http://www.ietf.org'>IETF</ulink>">
<!ENTITY im "<acronym>IM</acronym>">
<!ENTITY smtp "<acronym>SMTP</acronym>">
<!ENTITY gnu "<ulink url='http://www.gnu.org'>GNU</ulink>">
<!ENTITY gpl "<ulink url='http://www.gnu.org/licenses/licenses.html#GPL'>GPL</ulink>">

<!-- Often used RFCs -->

<!ENTITY rfc3261 "<ulink url='http://www.ietf.org/rfc/rfc3261.txt'>RFC3261</ulink>">
<!ENTITY rfc822 "<ulink url='http://www.ietf.org/rfc/rfc822.txt'>RFC822</ulink>">
<!ENTITY rfc2543 "<ulink url='http://www.ietf.org/rfc/rfc2543.txt'>RFC2543</ulink>">