Improving Web Application Security: Threats and - CGISecurity

760 Improving Web Application Security: Threats and CountermeasuresAFD.SYS ProtectionsThe following keys specify parameters for the kernel mode driver Afd.sys. Afd.sys isused to support Windows sockets applications. All of the keys and values in thissection are located under the registry keyHKLM\System\CurrentControlSet\Services\AFD\Parameters. These keys andvalues are:● Value: EnableDynamicBacklogRecommended value data: 1Valid values: 0 (disabled), 1 (enabled)Description: Specifies AFD.SYS functionality to withstand large numbers ofSYN_RCVD connections efficiently. For more information, see “Internet ServerUnavailable Because of Malicious SYN Attacks,” athttp://support.microsoft.com/default.aspx?scid=kb;en-us;142641.●●●Value name: MinimumDynamicBacklogRecommended value data: 20Valid values: 0–4294967295Description: Specifies the minimum number of free connections allowed on alistening endpoint. If the number of free connections drops below this value, athread is queued to create additional free connectionsValue name: MaximumDynamicBacklogRecommended value data: 20000Valid values: 0–4294967295Description: Specifies the maximum total amount of both free connections plusthose in the SYN_RCVD state.Value name: DynamicBacklogGrowthDeltaRecommended value data: 10Valid values: 0–4294967295Present by default: NoDescription: Specifies the number of free connections to create when additionalconnections are necessary.