Cisco Router Slow internet Speed

[SilverAfter]

I'm using router 4321. The only service I have configured is NAT, but my internet speed is too slow. Below is what is configured on the device.

R1(config)#do sh run
Building configuration...

Current configuration : 6735 bytes
!
! Last configuration change at 05:18:30 UTC Sat Nov 30 2024
!
version 17.3
service timestamps debug datetime msec
service timestamps log datetime msec
! Call-home is enabled by Smart-Licensing.
service call-home
platform qfp utilization monitor load 80
platform punt-keepalive disable-kernel-core
platform hardware throughput level 100000
!
hostname R1
!
boot-start-marker
boot-end-marker
!
!
vrf definition Mgmt-intf
!
address-family ipv4
exit-address-family
!
address-family ipv6
exit-address-family
!
no aaa new-model
!
ip dhcp excluded-address 192.168.0.0 192.168.0.99
ip dhcp excluded-address 192.168.0.201 192.168.0.255
!
ip dhcp pool DHCP
network 192.168.0.0 255.255.255.0
dns-server 8.8.8.8 1.1.1.1
default-router 192.168.0.254
!
login on-success log
!
subscriber templating
!
multilink bundle-name authenticated
no device-tracking logging theft
!
crypto pki trustpoint TP-self-signed-406564953
enrollment selfsigned
subject-name cn=IOS-Self-Signed-Certificate-406564953
revocation-check none
rsakeypair TP-self-signed-406564953
!
crypto pki trustpoint SLA-TrustPoint
enrollment pkcs12
revocation-check crl
!
no license feature hseck9
license udi pid ISR4321/K9 sn FDO20531YW6
license boot level appxk9 disable
memory free low-watermark processor 69063
!
diagnostic bootup level minimal
!
spanning-tree extend system-id
!
!
redundancy
mode none
!
interface GigabitEthernet0/0/0
ip address 192.168.0.254 255.255.255.0
ip nat inside
negotiation auto
!
interface GigabitEthernet0/0/1
ip address dhcp
ip nat outside
negotiation auto
!
interface Serial0/1/0
shutdown
!
interface Serial0/1/1
shutdown
!
interface GigabitEthernet0
vrf forwarding Mgmt-intf
no ip address
shutdown
negotiation auto
!
ip http server
ip http authentication local
ip http secure-server
ip forward-protocol nd
ip tftp source-interface GigabitEthernet0
ip nat inside source list NAT interface GigabitEthernet0/0/1 overload
!
ip access-list extended NAT
10 permit ip any any
!
control-plane
!
mgcp behavior rsip-range tgcp-only
mgcp behavior comedia-role none
mgcp behavior comedia-check-media-src disable
mgcp behavior comedia-sdp-force disable
!
mgcp profile default
!
line con 0
stopbits 1
line aux 0
stopbits 1
line vty 0 4
login
transport input ssh
!
call-home
! If contact email address in call-home is configured as sch-smart-licensing@cisco.com
! the email address configured in Cisco Smart License Portal will be used as contact email address to send SCH notifications.
contact-email-addr sch-smart-licensing@cisco.com
profile "CiscoTAC-1"
active
destination transport-method http
!
end

[shambhu.kumar · Accepted solution]

Hello,

Please check NAT Translation entry, Is it getting exceeded?
Default Aggregate Throughput of ISR 4321 is 50 Mbps, you can get a Performance-on-Demand License (FL-4320-PERF-K9)to upgrade so it can support 100 Mbps.

You can verify the throughput by "sh platform hardware throughput level"

Thanks

[Flavio Miranda]

@SilverAfter 

 4321 is a very decent device and unless you put is as a front node for a very large company, which I am pretty sure you did not. I dont believe this is your problem.

Your NAT config could be better.

ip access-list extended NAT
10 permit ip any any
!

I would specify the source instead any.  This way of configuring may cause issue as any interface with layer3 capability you would add on this router will perform NAT and not always we want that.

 But this is surelly not your problem. After all, currently, you only have one interface.

Blame a router for slow internet  is not fair. There are so many blocks until the traffic gets to the far end.  For the router, I would take a look on the CPU and memory and that´s it. Rather than that, I would blame the ISP or your PC.