Kingsley,

That's wrong. Based on your logic one could not filter components of HTTP
requests (uri, host, body content, etc.) from the outside/internet towards
the inside/server segment. This is false, in fact it's something that I
implement on ASA firewalls quite often. You seem to be confused about the
idea of inbound/outbound packet flow through an interface policy-map versus
connections moving either lower-to-higher or higher-to-lower.
While it may be true that SOME app inspects are dependent upon security
levels, HTTP and FTP, at least in respect to policy-maps via MPF, are not.

Regards,
Buck Wallander

On Thu, Sep 30, 2010 at 12:40 AM, Kingsley Charles <
[email protected]> wrote:

> Outbound means from Higher security to lower security
> Inbound means from Lower to higher security
>
>
> Irrespective of whether the policy map is applied to inside, outside or
> global the "Outbound" and "Inbound" logic will not change.
>
> Now if you read the following snippet from
> http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/intparam.html#wp1057744,
> you can see that some inspections are dependent on the security levels.
>
>
>
> Inspection engines—Some application inspection engines are dependent on the
> security level. For same security interfaces, inspection engines apply to
> traffic in either direction.
>
> NetBIOS inspection engine—Applied only for outbound connections.
>
> SQL*Net inspection engine—If a control connection for the SQL*Net (formerly
> OraServ) port exists between a pair of hosts, then only an inbound data
> connection is permitted through the security appliance.
>
> Filtering—HTTP(S) and FTP filtering applies only for outbound connections
> (from a higher level to a lower level).
>
> If you enable communication for same security interfaces, you can filter
> traffic in either direction.
>
>
> With regards
> Kings
>
> On Thu, Sep 30, 2010 at 9:23 AM, Buck Wallander <[email protected]> wrote:
>
>> Just another bit of clarification on this topic so that others aren't
>> confused. The document that you linked is referring to the anti-X filtering
>> of HTTP and FTP, ie. when using the "FILTER" command for FTP and HTTP.
>>
>> Security levels have no bearing on the actual INSPECTS for ftp and http
>> (inspect http & inspect ftp), which will inspect traffic bidirectionally when
>> applied directly to an interface, or 'ingress only' when applied globally
>> via a service-policy, just like most other protocol inspects.
>>
>> Regards,
>> Buck Wallander
>>
>>
>> On Fri, Sep 24, 2010 at 9:25 AM, Anantha Subramanian Natarajan <
>> [email protected]> wrote:
>>
>>> Thanks Kings
>>>
>>> Regards
>>> Anantha Subramanian Natarajan
>>>
>>>
>>> On Fri, Sep 24, 2010 at 1:20 AM, Kingsley Charles <
>>> [email protected]> wrote:
>>>
>>>> It seems that for some application inspections are not bidirectional.
>>>> For example the ASA applies http and ftp filtering for outbound connections
>>>> and not for
>>>> inbound. It's ASA limitation.
>>>>
>>>>
>>>> Snippet from
>>>> http://www.cisco.com/en/US/docs/security/asa/asa80/configuration/guide/intparam.html#wp1057744
>>>>
>>>> Inspection engines—Some application inspection engines are dependent on
>>>> the security level. For same security interfaces, inspection engines apply
>>>> to traffic in either direction.
>>>>
>>>> NetBIOS inspection engine—Applied only for outbound connections.
>>>>
>>>> SQL*Net inspection engine—If a control connection for the SQL*Net
>>>> (formerly OraServ) port exists between a pair of hosts, then only an 
>>>> inbound
>>>> data connection is permitted through the security appliance.
>>>>
>>>> Filtering—HTTP(S) and FTP filtering applies only for outbound
>>>> connections (from a higher level to a lower level).
>>>>
>>>> If you enable communication for same security interfaces, you can filter
>>>> traffic in either direction.
>>>>
>>>>
>>>>
>>>> With regards
>>>>
>>>> Kings
>>>>
>>>>
>>>> On Wed, Sep 22, 2010 at 10:00 PM, Anantha Subramanian Natarajan <
>>>> [email protected]> wrote:
>>>>
>>>>> Hi All,
>>>>>
>>>>>   Was going through the Cisco ASA config guide and understanding that
>>>>> *some *application inspection engines are dependent on the security
>>>>> level.I am trying to understand the relation between inspection engines 
>>>>> and
>>>>> the security-level and also why only some application inspection engine
>>>>> depends on the security level.
>>>>>
>>>>> If you could explain or point to me a proper documentation,would really
>>>>> appreciate that.
>>>>>
>>>>> Regards
>>>>> Anantha Subramanian Natarajan
>>>>>
>>>>> _______________________________________________
>>>>> For more information regarding industry leading CCIE Lab training,
>>>>> please visit www.ipexpert.com
>>>>>
>>>>>
>>>>
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training, please
>>> visit www.ipexpert.com
>>>
>>>
>>
>
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