Robtex

Up: 200.23.138.0/23
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Down left: 200.23.139.0/25
Down right: 200.23.139.128/25
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
200.23.139.13	PTR	mta1a.pmailitesm.zscaler.net
200.23.139.14	PTR	mta1a-out-s1.pmailitesm.zscaler.net
200.23.139.17	PTR	mta1a-out-s4.pmailitesm.zscaler.net
200.23.139.18	PTR	qtn1a-out-s1.pmailitesm.zscaler.net
200.23.139.19	A+PTR	prd18wtyc01.sistematec.mx
200.23.139.19	PTR	mta1a-out.pmailitesm.zscaler.net
200.23.139.20	A+PTR	bpmsvr01.itesm.mx
200.23.139.20	PTR	mta1a-out-u1.pmailitesm.zscaler.net
200.23.139.23	A+PTR	fstest.itesm.mx
200.23.139.23	PTR	mta1b.pmailitesm.zscaler.net
200.23.139.24	A+PTR	mta1b-out-s1.pmailitesm.zscaler.net
200.23.139.25	PTR	mta1b-out-s2.pmailitesm.zscaler.net
200.23.139.26	PTR	mta1b-out-s3.pmailitesm.zscaler.net
200.23.139.27	PTR	mta1b-out-s4.pmailitesm.zscaler.net
200.23.139.28	PTR	colabora.itesm.mx
200.23.139.28	A+PTR	comparte.itesm.mx
200.23.139.28	A+PTR	consejerosftv.itesm.mx
200.23.139.29	A+PTR	alsvdes01.itesm.mx
200.23.139.29	PTR	mta1b-out.pmailitesm.zscaler.net
200.23.139.32	A	as2c.itesm.mx
200.23.139.33	A+PTR	prd28pi01.itesm.mx
200.23.139.33	PTR	qtn1a.pmailitesm.zscaler.net
200.23.139.34	A+PTR	pre28pi01.itesm.mx
200.23.139.34	PTR	qtn1a-out.pmailitesm.zscaler.net
200.23.139.35	A	digitalizacion.itesm.mx
200.23.139.41	A	*.com.millenium.itesm.mx
200.23.139.41	A	millenium.itesm.mx
200.23.139.41	A	groups.yahoo.com.millenium.itesm.mx
200.23.139.48	A+PTR	gestordepagos.itesm.mx
200.23.139.51	PTR	mitec.itesm.mx
200.23.139.80	A	ssbutm.tecmilenio.mx
200.23.139.83	A+PTR	sip.itesm.mx
200.23.139.83	PTR	sip.sorteostec.mx
200.23.139.83	A+PTR	sip.clases.itesm.mx
200.23.139.86	A+PTR	sip.itesm.mx
200.23.139.86	PTR	sip.sorteostec.mx
200.23.139.86	A+PTR	sip.clases.itesm.mx