My final choise is the creation of a trigger. I post this in the case someone else want to avoid the inserting of local ip addresses in sitelog table:
CREATE TRIGGER ExclusionOfLocaIPAddresses ON [dbo].[SiteLog]
INSTEAD OF INSERT
AS
DECLARE @UserHostAddress as nvarchar(255)
SET @UserHostAddress = (SELECT UserHostAddress FROM Inserted)
IF NOT (
@UserHostAddress = '127.0.0.1' OR
(CHARINDEX('192.168.1.', @UserHostAddress, 0) = 1 AND CHARINDEX('.', @UserHostAddress, 13) = 0 )
)
BEGIN
INSERT INTO SiteLog (DateTime, PortalId, UserId, Referrer, Url, UserAgent, UserHostAddress, UserHostName, TabId, AffiliateId)
SELECT
DateTime, PortalId, UserId, Referrer, Url, UserAgent, UserHostAddress, UserHostName, TabId, AffiliateId FROM Inserted
END