snmp mac address and if index query

i normally query for all arp entries using the

RFC1213-MIB

mib and

ipNetToMediaPhysAddress

or

ipNetToPhysicalPhysAddress

oid; the typical output is something like:

IP-MIB::ipNetToPhysicalPhysAddress.13.ipv4."172.18.x.y" = STRING: 0:d0:ff:ee:fc:a
IP-MIB::ipNetToPhysicalPhysAddress.14.ipv4."127.2.0.1" = STRING: 0:23:e9:6e:97:0
IP-MIB::ipNetToPhysicalPhysAddress.17.ipv4."127.1.1.2" = STRING: 0:1:23:45:67:0
IP-MIB::ipNetToPhysicalPhysAddress.17.ipv4."127.1.1.3" = STRING: 0:1:23:45:67:1
IP-MIB::ipNetToPhysicalPhysAddress.17.ipv4."127.1.1.4" = STRING: 0:1:23:45:67:2
IP-MIB::ipNetToPhysicalPhysAddress.17.ipv4."127.1.1.5" = STRING: 0:1:23:45:67:3
IP-MIB::ipNetToPhysicalPhysAddress.19.ipv4."a.b.c.d" = STRING: 0:0:c:7:ac:97

(first an last ip's redacted)

the number before the ipv4 bit usually corresponds to the ifIndex of the interface that the arp was seen on. however, on our ltm box:

IF-MIB::ifIndex.80 = INTEGER: 80
IF-MIB::ifIndex.736 = INTEGER: 736
IF-MIB::ifIndex.752 = INTEGER: 752
IF-MIB::ifIndex.768 = INTEGER: 768
IF-MIB::ifIndex.784 = INTEGER: 784
IF-MIB::ifIndex.800 = INTEGER: 800
IF-MIB::ifIndex.816 = INTEGER: 816
IF-MIB::ifIndex.832 = INTEGER: 832
IF-MIB::ifIndex.848 = INTEGER: 848
IF-MIB::ifIndex.864 = INTEGER: 864
IF-MIB::ifIndex.880 = INTEGER: 880
IF-MIB::ifIndex.896 = INTEGER: 896
IF-MIB::ifIndex.912 = INTEGER: 912
IF-MIB::ifIndex.928 = INTEGER: 928

(as you can see the index's don't match).

how can i match the ifIndex value from

ipNetToPhysicalPhysAddress

to a real physical description like that presented with

sysInterfaceName

?