How to configure Mail Postfix with Dovecot on Linux

1. RequirementPostfix, Qpopper, Mailx, Mailman, Apache2, PHP5, Dovecot2. Configure Postfixvim /etc/postfix/main.cfmail_spool_directory = /var/mailcanonical_maps = hash:/etc/postfix/canonicalvirtual_alias_maps = hash:/etc/postfix/virtualvirtual_alias_domains = hash:/etc/postfix/virtualrelocated_maps = hash:/etc/postfix/relocatedtransport_maps = hash:/etc/postfix/transportsender_canonical_maps = hash:/etc/postfix/sender_canonicalmasquerade_exceptions = rootmasquerade_classes = envelope_sender, header_sender, header_recipientmyhostname = linux.meanchey.comprogram_directory...

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Unstructured Supplementary Services Data (USSD)

Unstructured Supplementary Services Data (USSD) allows for the transmission of information via a GSM network. Contrasting with SMS, it offers real time connection during a session. A USSD message can be upto 182 alphanumeric characters in length. Unstructured Supplementary Service Data allows interactive services between a MS and applications hosted by the Mobile Operator. These messages are composed of digits and the #, * keys, and allow users to easily and quickly get information/access services from the Operator. USSD messages are simple to...

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ISUP (ISDN User Part)

ISUP (ISDN User Part) defines the messages and protocol used in the establishment and tear down of voice and data calls over the public switched telephone network (PSTN), and to manage the trunk network on which they rely. Despite its name, ISUP is used for both ISDN and non–ISDN calls. In the North American version of SS7, ISUP messages rely exclusively on MTP to transport messages between concerned nodes. ISUP controls the circuits used to carry either voice or data traffic. In addition, the state of circuits can be verified and managed using...

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Intelligent Network Application Part (INAP)

Intelligent Network Application Part (INAP) is the signaling protocol used in Intelligent Networking. Developed by the International Telecommunications Union (ITU), IN is recognized as a global standard. Within the International Telecommunications Union, a total functionality of the IN has been defined and implemented in digestible segments called capability sets. The first version to be released was Capability Set 1 (CS-1). Currently CS-2 is defined and available. The CAMEL Application Part (CAP) is a derivative of INAP and enables the use of...

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Transaction Capabilities Application Part (TCAP)

Transaction Capabilities Application Part (TCAP) defines the messages and protocol used to communicate between applications (deployed as subsystems) in nodes. It is used for database services such as calling card, 800, and AIN as well as switch-to-switch services including repeat dialing and call return. Because TCAP messages must be delivered to individual applications within the nodes they address, they use the SCCP for transport. TCAP enables the deployment of advanced intelligent network services by supporting non-circuit related information...

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Signaling Connection Control Part (SCCP)

The Signaling Connection Control Part (SCCP) layer of the SS7 stack provides provides connectionless and connection-oriented network services and global title translation (GTT) capabilities above MTP Level 3. SCCP is used as the transport layer for TCAP-based services. It offers both Class 0 (Basic) and Class 1 (Sequenced) connectionless services. SCCP also provides Class 2 (connection oriented) services, which are typically used by Base Station System Application Part, Location Services Extension (BSSAP-LE). In addition, SCCP provides...

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Message Transfer Part (MTP)

The Message Transfer Part (MTP) layer of the SS7 protocol provides the routing and network interface capabilities that support SCCP, TCAP, and ISUP. Message Transfer part (MTP) is divided into three levels. MTP Level 1 (Physical layer) defines the physical, electrical, and functional characteristics of the digital signaling link. Physical interfaces defined include E-1 (2048 kb/s; 32 64 kb/s channels), DS-1 (1544 kb/s; 24 64 kp/s channels), V.35 (64 kb/s), DS-0 (64 kb/s), and DS-0A (56 kb/s). MTP Level 2 provides the reliability aspects...

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SS7 Signaling System #7

Resource from http://www.telecomspace.com/There are two essential components to all telephone calls. The first, and most obvious, is the actual content—our voices, faxes, modem data, etc. The second is the information that instructs telephone exchanges to establish connections and route the “content” to an appropriate destination. Telephony...

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