When we install SQL Server, SQL Server requires some of permissions like TSQL Local Machine, TSQL Named Pipes, TSQL Default TCP and TSQL Default VIA, by which other clients could also access SQL Server.
-- 014. Who has CONNECT permission for an endpoint script - SQL Server
SELECT EP.name, SP.STATE,
CONVERT(nvarchar(38), suser_name(SP.grantor_principal_id))
AS GRANTOR,
SP.TYPE AS PERMISSION,
CONVERT(nvarchar(46),suser_name(SP.grantee_principal_id))
AS GRANTEE
FROM sys.server_permissions SP , sys.endpoints EP
WHERE SP.major_id = EP.endpoint_id
ORDER BY Permission,grantor, grantee;
GO