{"id":531,"date":"2021-09-01T09:53:02","date_gmt":"2021-09-01T09:53:02","guid":{"rendered":"https:\/\/www.practicallynetworked.com\/?page_id=531"},"modified":"2021-10-05T17:00:00","modified_gmt":"2021-10-05T17:00:00","slug":"specialapps","status":"publish","type":"post","link":"https:\/\/www.practicallynetworked.com\/specialapps\/","title":{"rendered":"Handling Special Applications"},"content":{"rendered":"<p><b><span style=\"font-family: Arial; font-size: medium;\">Special? What&#8217;s special?<br \/>\n<\/span><\/b><\/p>\n<p>A &#8220;special application&#8221; is one that doesn&#8217;t work with the default settings of your Internet sharing method.\u00a0 Depending on the sharing method you use and the applications you run, you can have a lot of &#8220;specials&#8221; or none at all.\u00a0 To narrow things down a bit, here are some rules of thumb:<\/p>\n<ul>\n<li><b>If you use the Multiple IP method of sharing<\/b>, you\u00a0<i>won&#8217;t have any<\/i>\u00a0&#8220;Special Applications&#8221; because every computer is connected directly to the Internet and has its own IP address.\u00a0 So, no sharing!<\/li>\n<li><b>If you use a Proxy sharing method<\/b>, that uses a\u00a0<i>classic proxy server<\/i>\u00a0(and not one of the &#8220;redirection&#8221; protocols that many proxies use today in order to appear more &#8220;NAT&#8221; like) you&#8217;ll tend to have a\u00a0<b><i>lot<\/i><\/b>\u00a0of &#8220;Special Applications&#8221; (in addition to having to play with the settings of each application to configure them for proxy use).<\/li>\n<li><b>If you use a NAT sharing method, a hardware router, or a Proxy-with-redirector,<\/b>\u00a0the number of special applications you have and which ones they are will vary.<\/li>\n<\/ul>\n<p>Since the way of the world seems to be leaning toward NAT based sharing, we&#8217;ll be focusing on that method.<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<table border=\"0\" width=\"120\" cellspacing=\"2\" cellpadding=\"0\" align=\"right\" bgcolor=\"#385CA0\">\n<tbody>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/clientcfg.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Configure Clients<\/b><\/span><\/a><\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/securnet.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Secure LAN<\/b><\/span><\/a><\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/support\/troubleshoot_index.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Troubleshoot<\/b><\/span><\/a><\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/specialapps.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Special Applications<\/b><\/span><\/a><\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\">\n<p align=\"left\"><span style=\"color: #ffffff;\"><b class=\"LINK\">\u00a0\u00a0\u00a0\u00a0 &#8211;<\/b><\/span><a href=\"https:\/\/www.practicallynetworked.com\/app_ports.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Opening Ports<\/b><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\">\n<p align=\"left\"><span style=\"color: #ffffff;\"><b class=\"LINK\">\u00a0\u00a0\u00a0\u00a0 &#8211;<\/b><\/span><a href=\"https:\/\/www.practicallynetworked.com\/app_port_list.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Port List<\/b><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\">\n<p align=\"left\"><span style=\"color: #ffffff;\"><b class=\"LINK\">\u00a0\u00a0\u00a0\u00a0 &#8211;<\/b><\/span><a href=\"https:\/\/www.practicallynetworked.com\/app_ports.htm#References\"><span style=\"color: #ffffff;\"><b class=\"LINK\">References<\/b><\/span><\/a><\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/otherinfo.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Other Info<\/b><\/span><\/a><\/td>\n<\/tr>\n<tr>\n<td valign=\"middle\" bgcolor=\"#385CA0\"><a href=\"https:\/\/www.practicallynetworked.com\/prxysum.htm\"><span style=\"color: #ffffff;\"><b class=\"LINK\">Summary<\/b><\/span><\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>&nbsp;<\/p>\n<p><span style=\"font-family: Arial;\"><b>A note for\u00a0<a name=\"Wingate\"><\/a>Wingate and other proxy users<\/b><\/span><\/p>\n<p>Proxy-based sharing requires setting up a UDP or TCP mapping service for each Special Application.\u00a0 The basic information on how to do this with the\u00a0<b>original Wingate (2.X)<\/b>\u00a0or\u00a0<b>Wingate 3.X&#8217;s Standard or Pro&#8217;s Proxy Service<\/b>\u00a0can be found\u00a0<b><a href=\"http:\/\/kb.deerfield.com\/index.cfm?a=1057&amp;k=1&amp;CFID=167917&amp;CFTOKEN=83328949\" target=\"_blank\" rel=\"noopener\">in Wingate Knowledge Base Article 1057<\/a><\/b>.\u00a0 A how-to for setting up a\u00a0<b>Dialpad<\/b>\u00a0mapping can be found in\u00a0<b><a href=\"http:\/\/kb.deerfield.com\/index.cfm?a=1556&amp;k=1&amp;CFID=167917&amp;CFTOKEN=83328949\" target=\"_blank\" rel=\"noopener\">Article 1556<\/a><\/b>.\u00a0 You can also\u00a0<b><a href=\"http:\/\/kb.deerfield.com\/index.cfm?q=mapping&amp;st=1&amp;sb=4&amp;sh=1&amp;sc=10&amp;d=7&amp;w=WinGate_All&amp;so=Title&amp;ad=ASC&amp;sp=1\" target=\"_blank\" rel=\"noopener\">click here<\/a><\/b>\u00a0to get a listing of Wingate Knowledge Base Articles that deal with port mapping.<\/p>\n<p><b><i><span style=\"color: #0000ff;\">Note that you can&#8217;t map ports with Wingate 3.X Home or when using Wingate 3.X&#8217;s WRP method.<\/span><\/i><\/b><\/p>\n<p>For other proxy programs, the approach is the same as with Wingate, but the details of doing the mapping will be different.\u00a0 Consult your program&#8217;s Help or FAQ pages.<br \/>\n<b><span style=\"font-family: Arial; font-size: medium;\">Your Friend, the NAT firewall<\/span><\/b><\/p>\n<p>NAT routers have a natural firewall that rejects any\u00a0<b><i>unsolicited<\/i><\/b>\u00a0data that tries to travel from the Internet to a computer on your LAN.\u00a0 Basically, if you didn&#8217;t ask for the data, it isn&#8217;t gonna get past the firewall. A few examples may help:<\/p>\n<ul>\n<li>\n<p align=\"left\">Applications like Web browsing, and email work fine through the NAT firewall because in each case, you\u00a0<i>ask<\/i>\u00a0for a web page or\u00a0<i>ask<\/i>\u00a0to send or receive email.<\/p>\n<\/li>\n<li>\n<p align=\"left\">If you try to run a web server on one of the computers behind the NAT firewall, it won&#8217;t be accessible because the requests for data\u00a0<i>are not originating from a machine on your LAN<\/i>, but from a machine out on the Internet.<\/p>\n<\/li>\n<li>\n<p align=\"left\">Messaging applications like AIM, ICQ, Netmeeting, Dialpad and others might be able to\u00a0<i>originate<\/i>\u00a0calls or chat sessions, but may not be able to\u00a0<i>receive<\/i>\u00a0calls, because receiving calls means that the data request didn&#8217;t start out from a machine on your network.<\/p>\n<\/li>\n<\/ul>\n<p><b><span style=\"font-family: Arial; font-size: medium;\"><br \/>\nJust another hole in the wall<\/span><\/b><\/p>\n<p>So what do you want to do if you want to receive data\u00a0<i>originating<\/i>\u00a0from the Internet?\u00a0 The answer goes by many names, i.e. port mapping, port forwarding, DMZ, application rules, etc.\u00a0 But they all boil down to opening holes in the firewall so that unrequested data can come into selected computers on your LAN.<\/p>\n<p>Notice that I said\u00a0<i>unrequested<\/i>\u00a0data.\u00a0 In light of all the media articles about Internet security, that might make you want to stop right here and leave that firewall intact!\u00a0 However, it\u00a0<i>is<\/i>\u00a0possible to be secure and have your favorite applications work, but it takes some work and you have to be careful to do things right.<\/p>\n<p><img alt='attentionsml-1855421' src='https:\/\/www.practicallynetworked.com\/wp-content\/uploads\/2021\/09\/attentionsml-1855421.gif' alt=\"attentionsml.gif (1034 bytes)\" width=\"30\" height=\"30\" border=\"0\" \/><span style=\"color: #ff0000;\"><b>Opening holes in your firewall,\u00a0 can compromise your LAN&#8217;s security if done incorrectly. Please\u00a0<a>read this information on Security<\/a>\u00a0before proceeding.<\/b><\/span><\/p>\n<p>Rule #3<b>\u00a0&#8220;Open only the ports you need&#8221;<\/b>\u00a0is the most relevant to the subject of opening special application ports, so keep it in mind when you&#8217;re deciding whether you really need to open that firewall hole.<b><span style=\"font-family: Arial; font-size: medium;\"><br \/>\nOne\u00a0<a name=\"port\"><\/a>port per customer!<\/span><\/b><\/p>\n<p>Port mapping through a firewall isn&#8217;t a substitute for having a computer connected directly to the Internet.\u00a0 Another rule of thumb may help:<\/p>\n<p><b><i>Only one computer inside the firewall can use a specific\u00a0<\/i>inbound<i>\u00a0port at a time.<\/i><\/b><\/p>\n<p>If all Internet applications used only one\u00a0<b><i>unique<\/i><\/b>\u00a0port, there wouldn&#8217;t be much confusion about how all this port mapping stuff works.\u00a0\u00a0<b>But<\/b>, not all applications work that way.\u00a0 Many applications (<b>messaging<\/b>\u00a0and\u00a0<b>gaming<\/b>\u00a0applications in particular) use multiple ports and groups of ports, and are generally the hardest to get working behind a firewall.\u00a0 Other applications, like\u00a0<b>MS Netmeeting<\/b>\u00a0are pretty much impossible to get working behind a firewall because they use multiple ports, port ranges, dynamically assigned ports, and special protocols.\u00a0 For these applications, you&#8217;ll just have to place the computer that you want to run the application on outside the firewall, either physically, or via your router&#8217;s &#8220;DMZ&#8221; or &#8220;Exposed Computer&#8221; feature.<\/p>\n<p><b><span style=\"font-family: Arial; font-size: medium;\">Pull the\u00a0<a name=\"trigger\"><\/a>trigger<\/span><\/b><\/p>\n<p>Some routers try to get around this &#8220;one port per customer&#8221; limitation by using &#8220;triggered&#8221; maps.\u00a0 Triggered maps work by having the router watch\u00a0<b><i>outgoing<\/i><\/b>\u00a0data for a specific port number and protocol.\u00a0 When the router sees a match, it remembers the IP address of the computer that sent the matching data.\u00a0 When the requested data wants to come back\u00a0<b><i>in<\/i><\/b>\u00a0through the firewall, the router uses the port mapping rules that are linked to the trigger, and the IP address of the computer that &#8220;pulled&#8221; the trigger, to get the data back to the proper computer.<\/p>\n<p>These triggered events can be timed so that they erase the port mapping as soon as they are done with the data transfer, so that the port map can be triggered by another Client computer.\u00a0 This gives the\u00a0<b><i>illusion<\/i><\/b>\u00a0that multiple computers can use the same port mapping at the same time, but the computers are really just taking turns using the mapping.<\/p>\n<p><img alt='attentionsml-1855421' src='https:\/\/www.practicallynetworked.com\/wp-content\/uploads\/2021\/09\/attentionsml-1855421.gif' alt=\"attentionsml.gif (1034 bytes)\" width=\"30\" height=\"30\" border=\"0\" \/><b><i>Two important limitations of triggered maps!<\/i><\/b><\/p>\n<ol>\n<li>\n<p align=\"left\"><b>The trigger event comes from a computer\u00a0<i>inside<\/i>\u00a0the firewall.<\/b><br \/>\nTrigger events can&#8217;t happen on data coming from\u00a0<b><i>outside<\/i><\/b>\u00a0the firewall because the NAT router&#8217;s sharing function doesn&#8217;t work in that direction.<\/p>\n<\/li>\n<li>\n<p align=\"left\"><b>The more an application needs to have a\u00a0<i>continuous<\/i>\u00a0data stream, the less likely that triggered maps are going to help.<\/b><br \/>\nThis is because the continuous data stream ties up the port mapping so that it can&#8217;t be triggered by another computer.\u00a0\u00a0<b><br \/>\nRemember: Only one computer can use a port or port range at a time on a given real (ISP assigned) IP address!<\/b><\/p>\n<\/li>\n<\/ol>\n<p align=\"left\">Routers that have this &#8220;triggered map&#8221; capability include:<\/p>\n<ul>\n<li>\n<p align=\"left\"><b><a href=\"http:\/\/www.sygate.com\/cgi-bin\/affiliate.cgi?oemcode=H1001003\" target=\"_blank\" rel=\"noopener\">Sygate<\/p>\n<p><\/a><\/b><\/p>\n<\/li>\n<li>\n<p align=\"left\"><b>Nexland&#8217;s\u00a0<\/b><b><a href=\"https:\/\/www.practicallynetworked.com\/review.asp?pid=331\">ISB2LAN-H4<\/a>\u00a0<\/b>(called Special Applications)<b><\/p>\n<p><\/b><\/p>\n<\/li>\n<li>\n<p align=\"left\"><b>UMAX&#8217;s UGate series (<a href=\"https:\/\/www.practicallynetworked.com\/reviews\/ugp.asp\">UGate Plus<\/a>,\u00a0<a href=\"https:\/\/www.practicallynetworked.com\/reviews\/ug3000.asp\">UG3000<\/a>, UG3200)<br \/>\n<\/b>(called Special Applications)<\/p>\n<\/li>\n<li>\n<p align=\"left\"><b><a href=\"https:\/\/www.practicallynetworked.com\/reviews\/kingston_router.asp\">Kingston&#8217;s KNR7TXD EtheRX<\/a><\/b>\u00a0(called Special Applications)<\/p>\n<\/li>\n<li>\n<p align=\"left\"><b><a href=\"https:\/\/www.practicallynetworked.com\/reviews\/asante_router.asp\">Asante&#8217;s FR3004 series FriendlyNET<\/a><\/b>\u00a0(called Popular Applications)<\/p>\n<\/li>\n<li>\n<p align=\"left\"><b><a href=\"http:\/\/www.smc.com\/\" target=\"_blank\" rel=\"noopener\">SMC&#8217;s Barricade<\/a><\/b>\u00a0(called Popular Applications)<\/p>\n<\/li>\n<li>\n<p align=\"left\"><b><a href=\"https:\/\/www.practicallynetworked.com\/review.asp?pid=306\">2Wire&#8217;s Home Portal series<\/a><\/b><\/p>\n<\/li>\n<li><b><a href=\"https:\/\/www.practicallynetworked.com\/reviews\/lil_linksys_router.asp\">Linksys BEFSR41 v.2<\/a>.<\/b><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p align=\"left\">\nSo you now should have your expectations properly adjusted about port mapping and know that it won&#8217;t be the solution for every need that you have, right?<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Special? What&#8217;s special? A &#8220;special application&#8221; is one that doesn&#8217;t work with the default settings of your Internet sharing method.\u00a0 Depending on the sharing method you use and the applications you run, you can have a lot of &#8220;specials&#8221; or none at all.\u00a0 To narrow things down a bit, here are some rules of thumb: If you use the Multiple IP method of sharing, you\u00a0won&#8217;t have any\u00a0&#8220;Special Applications&#8221; because every computer is connected directly to the Internet and has its own IP address.\u00a0 So, no sharing! If you use a Proxy sharing method, that uses a\u00a0classic proxy server\u00a0(and not one <\/p>\n","protected":false},"author":2,"featured_media":5597,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/posts\/531"}],"collection":[{"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/comments?post=531"}],"version-history":[{"count":0,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/posts\/531\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/media\/5597"}],"wp:attachment":[{"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/media?parent=531"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/categories?post=531"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.practicallynetworked.com\/wp-json\/wp\/v2\/tags?post=531"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}