Why does svchost.exe need to connect to the Internet
Service Host (Svchost.exe) is the Microsoft Generic Host Process, which acts as a host for other processes running from dynamic-link libraries (DLLs). Multiple entries for this process might be present in the Task Manager list.
The Svchost.exe file is located in the %SystemRoot%\System32 folder. When Application rules are configured in Comodo Firewall pro, Svchost.exe will have %SystemRoot%\System32\services.exe as the parent process.
Service Host (Svchost.exe) is a core piece of Windows XP code that collects a number of lower-level system-critical services and runs them in a common environment. By gathering multiple functions together, we can reduces boot time and system overhead and eliminate the need to run dozens of separate low-level services.
Depending upon the number of Windows system services you have enabled, Service Host may be responsible for the management of up to 47 services, not all of which require Internet connectivity.
Some of key Internet services for which Svchost.exe is responsible are:
Automatic Windows Updates - (Service Name) Wuauserv
Checks for updates and patches at the Windows Update site and downloads or installs them automatically if you have selected those options.
Background Intelligent Transfer Service - (Service Name) BITS
Used by Automatic Updates.
DHCP Client - (Service Name) Dhcp
Acquires an IP Address and other settings from a Dynamic Host Control Protocol (DHCP) server at startup.
DNS Client - (Service Name) Dnscache
Caches records of Domain Name System (DNS) lookups to improve performance.
Internet Connection Firewall (ICF) / Internet Connection Sharing (ICS) - (Service Name) SharedAccess
Provides Network Address Translation, address translation, and firewall services on networks.
SSDP Discovery Service - Service Name) SSDPSRV
ICF depends on UPnP to provide incoming connections to systems behind the firewall. If SSDP is disabled, you can’t use Remote Desktop and Remote Assistance to access systems across the Internet.
Universal Plug And Play Device Host - (Service Name) upnphost
See SSDP
Windows Time - (Service Name) W32Time
Allows you to synchronize the date and time on a computer with a remote server using options you set on the Internet Time tab of Control Panel, Date And Time.
There are others that may need access.
Svchost.exe is considered a safe application by Comodo Firewall Pro. The rules you may have to configure will depend upon your firewall settings.