Query for PSRAM in Ethernet with ESP32

[gcatesp]

Hi,
I have doubt about Ethernet PHY. As mentioned in official site , IP101pg is used as PHY with ESP_WROORER-B which has PSRAM.
But I planned to go with LAN8710A PHY with ESP-WROOM-32 , got confused about idea.

Question are follow:
1. My idea for LAN8710A PHY with ESP-WROOM-32 is valid ? can i follow it ?
2. What is used of PSRAM ? is that necessary for Ethernet interface ?

Thanks in advance
Gaurav