Dynamic Host Computer Protocol (DHCP) Tutorials

Dynamic Host Configuration Protocol (DHCP) is a protocol used by networked devices (clients) to obtain the parameters necessary for operation in an Internet Protocol network. This protocol reduces system administration workload, allowing devices to be added to the network with little or no manual configurations.
Dynamic Host Configuration Protocol is a way to manage network parameter assignment from a single DHCP server, or a group of DHCP servers arranged in a fault-tolerant manner. Even in small networks, Dynamic Host Configuration Protocol is useful because it can make it easy to add new machines to the local network.
DHCP is also recommended even in the case of servers whose addresses rarely change, so that if a server needs to be readdressed (RFC2071), changes can be made in as few places as possible. For devices such as routers and firewalls, that should not use DHCP, it can be useful to put Trivial File Transfer Protocol (TFTP) or SSH servers on the same machine that runs DHCP, which also serves to centralize administration.
DHCP can be used to assign addresses directly to servers and desktop machines, and, through a Point-to-Point Protocol (PPP) proxy, to dialup and broadband on-demand hosts, as well as for residential Network address translation (NAT) gateways and routers. DHCP is generally not appropriate for infrastructure such as non-edge routers and DNS servers.

E-mail hosting service

An email hosting service is an Internet hosting service that runs email servers.

Email hosting services usually offer premium email at a cost as opposed to advertising supported free Email Support or free webmail. Email hosting services thus differ from typical end-user email providers such as webmail sites. They cater mostly to demanding email users and Small and Mid Size (SME) businesses, while larger enterprises usually run their own email hosting service. Email hosting providers allow for premium email services along with custom configurations and large number of accounts. In addition, hosting providers manage user's own domain name, including any email authentication scheme that the domain owner wishes to enforce in order to convey the meaning that using a specific domain name identifies and qualifies email senders.

Most email hosting providers offer advanced premium email solutions hosted on dedicated custom email platforms. The technology and offerings of different email hosting providers can therefore vary with different needs. Email offered by most webhosting companies is usually more basic standardized POP3 based email and webmail based on open source webmail applications like Horde or Squirrelmail. Almost all webhosting providers offer standard basic email while not all email hosting providers offer webhosting.

Email Troubleshooting Tutorial

Email seems simple, but email delivery can fail at any number of places in its journey from the MUA (mail user agent) of the sender to the MUAs of the intended recipients. Delivery may be delayed in a mail queue somewhere in the network cloud, may fail because the email was deleted by a spam filter or rejected for being over file-size limits or having the wrong MIME type content...or the user may be embarrasses to realize that the email that mysteriously vanished is still sitting in their outbox.
Messages sent to mailing lists can be unexpectedly rejected or sent to moderation queues because the sender doesn't understand posting rules, which can vary from list to list and depend on how the sender is classified by each mailing list. Generally, the privilege of direct posting is limited to certain classes of known users to protect the list from spam. Users may think something is wrong when they are unable to post directly to a list when they are actually using a different account from the one under which the posting privileges were granted.
The need to troubleshoot email isn't limited to apparent delivery failure or delays. Sometimes users receive automated email messages they don't understand, or sometimes inappropriate messages get posted to a list.
The existence of so many variables yields so many potential failure points that even though email seems simple in principal, troubleshooting email is an inherently complex process. In the interests of empowering everyone in the online community who would like to understand more about email Support and possibly troubleshoot email themselves, this documentation addresses a wide audience from users experiencing issues when posting to a mailing list to mailing list administrators and site managers. It covers a broad range of topics specific to troubleshooting email but references material scattered throughout the Concepts, Appendix and Tools page help. The purpose of this introduction is to help you get a birds-eye-view of the available documentation, some suggestions as to what might be of most interest to you (depending on whether you are a website user or administrator), plus some pointers that we hope will guide you along the fastest path to the information you need to resolve your issue.

E-mail hosting service

An email hosting service is an Internet hosting service that runs email servers.

Email hosting services usually offer premium email at a cost as opposed to advertising supported free email or free webmail. Email hosting services thus differ from typical end-user email providers such as webmail sites. They cater mostly to demanding email users and Small and Mid Size (SME) businesses, while larger enterprises usually run their own email hosting service. Email hosting providers allow for premium email services and Email Support along with custom configurations and large number of accounts. In addition, hosting providers manage user's own domain name, including any email authentication scheme that the domain owner wishes to enforce in order to convey the meaning that using a specific domain name identifies and qualifies email senders.

Most email hosting providers offer advanced premium email solutions hosted on dedicated custom email platforms. The technology and offerings of different email hosting providers can therefore vary with different needs. Email offered by most webhosting companies is usually more basic standardized POP3 based email and webmail based on open source webmail applications like Horde or Squirrelmail. Almost all webhosting providers offer standard basic email while not all email hosting providers offer webhosting.