We can figure this standard access list

Question

We can figure this standard access list that's important remember that we use a standard access list  want to block all traffic or permit all traffic from a particular
source or destination let's take a look at this machine right here   that  is IP address say
640-554 we want to stop him from going into the Ethernet interface I'm the ad man he made me midsummer block callers traffic he can get out anymore maybe this is even the internet out
here we know people like their Internet access so to get back at them I'm a block it what I can do is I can use deny statement in my access list access list
one did not .
http://640-554cisco.com/

Answer 1

Hi Suresh,
ad 1) according to the documentation ( http://docs.oracle.com/cd/E28280_01/doc.1111/e26692/securityacls.htm#BEIIHJAH )
"At least one of the following must be true for a user to be granted a particular permission:
The user's name appears in the xClbraUserList metadata field with the appropriate permission.
The user belongs to a group that appears in the xClbraAliasList metadata field with the appropriate permission.
The user is part of an Enterprise role that appears in the xClbraRoleList metadata field with the appropriate permission."
meaning that OOTB a user will be granted both Read permission as per user-granted permissions and RWD as per group-granted permissions (resulting into RWD because at the same level a union operation is used).
I'd say that conceptually, the group assignment should not be used in your use-case, because you don't want to assign permissions to group's users, do you? You could create new groups, or use assignment of permissions per user.
ad 2) check this: http://docs.oracle.com/cd/E28280_01/doc.1111/e26692/securityacls.htm#BEIIDCGD
Using ACLs, regardless User or Group Access Lists, always impacts the performance. And, it is difficult to maintain. From the information at the link you may understand how it is implemented - basically, the execution of the query will be affected by: a) how many items have to be evaluated b) the length of strings (xClbraUserList, xClbraAliasList) to be evaluated.